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Uniparental markers of contemporary italian population reveals details on its pre-roman heritage

Brisighelli, Francesca; Álvarez Iglesias, Vanesa; Fondevila Álvarez, Manuel; Blanco Verea, Alejandro José; Carracedo Álvarez, Ángel; Pascali, Vincenzo L.; Capelli, Cristian; Salas Ellacuriaga, Antonio

Abstract

Background:According to archaeological records and historical documentation, Italy has been a melting point forpopulations of different geographical and ethnic matrices. Although Italy has been a favorite subject for numerouspopulation genetic studies, genetic patterns have never been analyzed comprehensively, including uniparental andautosomal markers throughout the country.Methods/Principal Findings:A total of 583 individuals were sampled from across the Italian Peninsula, from ten distant (ifhomogeneous by language) ethnic communities — and from two linguistic isolates (Ladins, Grecani Salentini). All sampleswere first typed for the mitochondrial DNA (mtDNA) control region and selected coding region SNPs (mtSNPs). This datawas pooled for analysis with 3,778 mtDNA control-region profiles collected from the literature. Secondly, a set of Y-chromosome SNPs and STRs were also analyzed in 479 individuals together with a panel of autosomal ancestry informativemarkers (AIMs) from 441 samples. The resulting genetic record reveals clines of genetic frequencies laid according to thelatitude slant along continental Italy – probably generated by demographical events dating back to the Neolithic. TheLadins showed distinctive, if more recent structure. The Neolithic contribution was estimated for the Y-chromosome as14.5% and for mtDNA as 10.5%. Y-chromosome data showed larger differentiation between North, Center and South thanmtDNA. AIMs detected a minor sub-Saharan component; this is however higher than for other European non-Mediterraneanpopulations. The same signal of sub-Saharan heritage was also evident in uniparental markers.Conclusions/Significance:Italy shows patterns of molecular variation mirroring other European countries, although someheterogeneity exists based on different analysis and molecular markers. From North to South, Italy shows clinal patterns thatwere most likely modulated during Neolithic times.

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Unipa en al Ma ke s o Con empo a y I alian Popula ion Re eals De ails on I s P e-Roman He i age F ancesca B isighelli 1,2,3. , Vanesa A ´l a ez-Iglesias 1 , Manuel Fonde ila 1 , Alejand o Blanco-Ve ea 1 , A ´ngel Ca acedo 1,4 , Vincenzo L. Pascali 2 , C is ian Capelli 3 , An onio Salas 1 * . 1Unidade de Xene ´ ica, Facul ade de Medicina, Ins i u o de Medicina Legal, Uni e sidade de San iago de Compos ela, Galicia, Spain, 2Fo ensic Gene ics Labo a o y, Ins i u e o Legal Medicine, Uni e si a `Ca olica del Sac o Cuo e, Rome, I aly, 3Depa men o Zoology, Uni e si y o Ox o d, Ox o d, Uni ed Kingdom, 4Fundacio ´nPu ´blica Galega de Medicina Xeno ´mica (FPGMX-SERGAS), CIBER en e medades a as, San iago de Compos ela, Galicia, Spain Abs ac Backg ound: Acco ding o a chaeological eco ds and his o ical documen a ion, I aly has been a mel ing poin o popula ions o di e en geog aphical and e hnic ma ices. Al hough I aly has been a a o i e subjec o nume ous popula ion gene ic s udies, gene ic pa e ns ha e ne e been analyzed comp ehensi ely, including unipa en al and au osomal ma ke s h oughou he coun y. Me hods/P incipal Findings: A o al o 583 indi iduals we e sampled om ac oss he I alian Peninsula, om en dis an (i homogeneous by language) e hnic communi ies — and om wo linguis ic isola es (Ladins, G ecani Salen ini). All samples we e i s yped o he mi ochond ial DNA (m DNA) con ol egion and selec ed coding egion SNPs (m SNPs). This da a was pooled o analysis wi h 3,778 m DNA con ol- egion p o iles collec ed om he li e a u e. Secondly, a se o Y- ch omosome SNPs and STRs we e also analyzed in 479 indi iduals oge he wi h a panel o au osomal ances y in o ma i e ma ke s (AIMs) om 441 samples. The esul ing gene ic eco d e eals clines o gene ic equencies laid acco ding o he la i ude slan along con inen al I aly – p obably gene a ed by demog aphical e en s da ing back o he Neoli hic. The Ladins showed dis inc i e, i mo e ecen s uc u e. The Neoli hic con ibu ion was es ima ed o he Y-ch omosome as 14.5% and o m DNA as 10.5%. Y-ch omosome da a showed la ge di e en ia ion be ween No h, Cen e and Sou h han m DNA. AIMs de ec ed a mino sub-Saha an componen ; his is howe e highe han o o he Eu opean non-Medi e anean popula ions. The same signal o sub-Saha an he i age was also e iden in unipa en al ma ke s. Conclusions/Signi icance: I aly shows pa e ns o molecula a ia ion mi o ing o he Eu opean coun ies, al hough some he e ogenei y exis s based on di e en analysis and molecula ma ke s. F om No h o Sou h, I aly shows clinal pa e ns ha we e mos likely modula ed du ing Neoli hic imes. Ci a ion: B isighelli F, A ´l a ez-Iglesias V, Fonde ila M, Blanco-Ve ea A, Ca acedo A ´, e al. (2012) Unipa en al Ma ke s o Con empo a y I alian Popula ion Re eals De ails on I s P e-Roman He i age. PLoS ONE 7(12): e50794. doi:10.1371/jou nal.pone.0050794 Edi o : Da id Ca amelli, Uni e si y o Flo ence, I aly Recei ed June 15, 2012; Accep ed Oc obe 24, 2012; Published Decembe 10, 2012 Copy igh : ß2012 B isighelli e al. This is an open-access a icle dis ibu ed unde he e ms o he C ea i e Commons A ibu ion License, which pe mi s un es ic ed use, dis ibu ion, and ep oduc ion in any medium, p o ided he o iginal au ho and sou ce a e c edi ed. Funding: The esea ch leading o hese esul s has ecei ed unding om he People P og amme (Ma ie Cu ie Ac ions) o he Eu opean Union’s Se en h F amewo k P og amme FP7/2007–2013/unde REA g an ag eemen numbe 290344, and he Minis e io de Ciencia e Inno acio ´n (SAF2008-02971 and SAF2011- 26983)(AS). CC and FB we e pa ially unded by he B i ish Academy o he p ojec ‘‘The G eeks in he Wes : he gene ic legacy o he colonisa ion in Sou h I aly and Sicily’’. The unde s had no ole in s udy design, da a collec ion and analysis, decision o publish, o p epa a ion o he manusc ip . Compe ing In e es s: The au ho s ha e decla ed ha no compe ing in e es s exis . * E-mail: [email p o ec ed]s .These au ho s con ibu ed equally o his wo k. In oduc ion I aly has his o ically been a con enien des ina ion o human popula ions mig a ing om A ica, he Middle Eas and Eu opean loca ions, in pa due o he geomo phological cha ac e is ics o he I alian Peninsula [1]. These g oups se led p e e en ially on he islands and coas al e i o ies [1] 500,000 yea s ago (ya), ha is, along he Lowe Paleoli hic, he longes pe iod o human p ehis o y, which was domina ed by he no able di usion o ools made om laked s one [2]. Al hough ich in ools and animal bones, only some o hese si es ha e p o ided a small quan i y o human skele al emains esembling hose om he mo e ecen si es o he Middle Paleoli hic, da ing o he Riss-Wu¨ m in e glacial pe iod and pa o he succeeding Wu¨ m glacia ion (ci ca 120,000 o 36,000 ya). These bones belong o a species named Homo sapiens neande halensis. [2] In his long Paleoli hic pe iod, na iga ion ac oss he Medi e anean was p obably a e and some p esen -day islands we e accessible ac oss land b idges la e co e ed by he ising sea [3]. Du ing he Uppe Paleoli hic, om 36,000 o 10,000 ya, he icecap expansion o he La e Glacial Maximum (LGM) pushed sou hwa d g oups o hun e s li ing in Cen al Eu opean a eas [1], and he Neande hals ga e way o he p esen species o man Homo sapiens sapiens du ing he inal phases o he Wu¨ m glacia ion. The nume ous aces om his pe iod a e pa icula ly ich in bu ials, animal bones and ools, he la e ha ing been wo ked wi h inc eased p ecision [2]. In he ew housand yea s o he ollowing Mesoli hic pe iod (ci ca 10,000 o 6,000 ya) he clima e con inued o g ow milde and si es om his pe iod ha e been ound h oughou he en i e I alian peninsula, being along he coas s in he plains and on he moun ains. Wi h PLOS ONE | www.plosone.o g 1 Decembe 2012 | Volume 7 | Issue 12 | e50794 he Neoli hic pe iod, om ci ca 6,000 BC o 2,800 BC, he adi ional hun ing and ga he ing economy was eplaced by he in oduc ion o ag icul u e, s ock ea ing, wea ing and po e y. This new cul u al in luence came pa icula ly om he Eas e n Medi e anean and he Nea Eas . Using he po e y p oduc ion abo e all, i has been possible o econs uc ai ly accu a ely he a ious phases o his complex pe iod [2]. Du ing he Coppe , B onze and I on ages, nume ous popula ion mo emen s occu ed be ween he Medi e anean basin and he Middle Eas [4]. Exchange o me als would de e mine he ans o ma ion o he i s social o ganiza ions in ancien ci iliza ions [4]. Sa dinia, Sicily and Tuscany we e among he i s I alian e i o ies o be occupied by humans due o hei s a egic loca ion and he p esence in hei e i o ies o impo an me al esou ces [5]. Di e en cul u es, ecognized on he basis o di e en a che- ological indings, se lemen s and bu ial adi ions, a ose in he pe iod be ween he Mesoli hic and I on Age. Be o e he Roman conques , ancien I aly was cha ac e ized only by he p esence o Indo-Eu opean popula ions [6] li ing in he I alian Peninsula since he second millennium BC, co esponding o he pe iod be ween he I on Age and Romaniza ion [2]. Du ing all his pe iod he e we e also inc easing con ac s wi h he Phoenician and G eek colonis s: he o me being la gely p esen on he coas s o Sa dinia and wes e n Sicily and he la e in Sou he n I aly. These colonies had a conside able in luence on he de elopmen o local cul u es ( om he Picenian o Campano-Samni e and he Apulian o B u io-Lucanian) [5]. The eco d o all he popula ions ha inhabi ed he I alian e i o y du ing (p e)-his o y is incomple e; many eco ds we e o unce ain loca ion and/o ambiguous denomina ion [6]. A he beginning o he i s millennium BC he ollowing na i e ibes could be dis inguished on he I alian e i o y: he Ligu es, on he coas ha bea s hei name, in he no he n Apennine alleys, pa o he p e-alpine alleys and he wes e n Po Valley; he Sicani, in he in e io o Sicily; and he I ali, in p esen -day Calab ia ( om whom comes he name ‘I aly’, which was o be ex ended o all he e i o y o he peninsula). Besides he al eady men ioned Te ama e ibe, on he sou he n edge o he Po Valley, and he Villano ans, p obably om Eas e n Eu ope who se led h ough- ou Cen al I aly, he e we e also he Umb ians o he eas o he uppe basin o he Tibe . The Vene i, who occupied he e i o y ha s ill bea s hei name, o iginally came om Illy ia as did he Messapii (now mode n Salen o o Sou h Apulia) and Iapyges, who se led in p esen -day Puglia (Apulia) [5]. Many o he popula ions o Cen al-Sou he n I aly we e c ea ed by he mixing o local and o eign elemen s da ing back o he p e ious millennium; i is he case o he Sabines and La ini who se led in Lazio oge he wi h Falisci, Aequi, Volsci, He nici and Ausones. The in e io o Ab uzzo was domina ed by he Ves ini, Paeligni and Ma si, while he cen al Ad ia ic coas was popula ed by Picen es, Ma ucini and F en ani. The Apennine a ea o Molise and Basilica a was peopled by he Samni es and Lucanians. In Calab ia and Sicily he e we e also he B u ii and Siculi. The Phoenician coloniza ion o he coas s o he Wes e n Medi e anean we e mainly limi ed in I aly o Sa dinia and wes e n Sicily and p eceded ha o he G eeks. I was ollowed by Punic se lemen s (T apani, Pale mo, Caglia i) linked o he ancien Phoenician colony o Ca hage. A he ime o he Roman Empi e, a leas wo non-Indo- Eu opean popula ions s ill inhabi ed I aly, namely, he Ligu es, in he no hwes e n a ea, and he E uscans wi h se lemen s loca ed in a eas a om he E u ia (Tuscany and High La ium), such as he Po Plain and he coas o Campania. A he same ime, Sa dinia expe ienced he lou ishing o a non-Indo-Eu opean Nu agic ci iliza ion and, hen, he Phoenician coloniza ion. Gene ics alone canno disen angle he ex emely complex demog aphy o I aly h ough his o y. Some demog aphic mo e- men s ha e howe e le signals on unipa en al and nuclea ma ke s. Mos o he gene ic s udies a ge ed local, e.g. [7], o egional, e.g. [8–11], I alian popula ions. Fo he Y-ch omosome, some a emp s ha e been unde aken o analyze I alian a ia ion o a mo e gene al scale [12–14]. Many s udies ha e analyzed speci ic haplog oups in he Y-ch omosomes, e.g. [15,16], o he m DNA, e.g. [8,9]. In gene al, he di e en s udies indica e ha he gene ic s uc u e o he p esen I alian popula ion seems o e lec , a leas in pa , he e hnic s a i ica ion o p e-Roman imes [14]. S udies ca ied ou in he pas appea o show a majo No h–Sou h cline consis en wi h a chaeological es ima es o wo dis inc p ocesses: he i s coloniza ion o he a ea du ing he Paleoli hic pe iod and he subsequen Neoli hic expansion om he Middle Eas a e he las glacial [14]. The e is some co espondence be ween pa e ns o a ia ion a he Y- ch omosome and geog aphy. Thus, no he n I aly shows simila equencies as he haplog oups o Cen al Eu ope, wi h p e alence o he wes e n R1-M173 haplog oup compa e o he eas e n I- M170. In he No h, E3b1-M35 and J2-M172 show low equencies bu a e mo e p e alen in he Sou h, which has been in e p e ed o be a signal o he gene low coming om Cen al Eu opean Neoli hic a me s [17]. R1a1-M17 is a he a e, bo h in he No h, whe e i p obably o igina es om eas e n Eu ope, and in he Sou h, o possible G eek p o enience [17]. Occu ence o J2-M172 Y-ch omosomes in Tuscany has been ela ed o he E uscan he i age o he egion (see [17]). The wo I alian majo islands, Sicily and Sa dinia, show a di e en demog aphic his o y. The Y-ch omosome a iabili y o Sicily sha es a common his o y wi h ha o sou he n I aly, en iched by an addi ional A ab con ibu ion, bu also No h A ican and G eek in luences [18]. On he o he hand, Sa dinia has been conside ed o be a gene ic ou lie wi hin Eu ope showing clea signals o ounde e ec s; some schola s sugges ha i s peoples could be o ancien Ibe ian o igin [19]; ecen gene ic s udies poin o gene ic con ibu ion coming om sou he n F ance [20]. On he o he hand, mi ochond ial DNA s udies show ha I aly does no di e oo much om o he Eu opean popula ions; howe e , some popula ions ha e he same peculia i ies and p ese e signals o he ancien pas demog aphic e en , such as he Tuscans [8,9], o he Ladins [7,21,22]. Recen ly, pa e ns o a ia ion obse ed in haplog oup U5b3 demons a ed o he i s ime he exis ence o a No h I alian p e-his o ical human e uge om he hos ile Cen al Eu opean egions co e ed by he ice o he Las Glacial Maximum pe iod [20]; his a ea, as was also he F anco-Can ab ian egion [23–26], se ed as a egion o Eu opean epopula ion du ing he beginning o he Holocene. The main aim o he p esen s udy was comp ehensi ely o analyze he pa e ns o m DNA and Y-ch omosome a ia ion in I aly. This s udy di e s om p e ious ones in ha : (1) i p o ides m DNA da a om 12 new sample popula ions om I aly; (2) we analyzed wo linguis ic isola es, Ladin and G ecani Salen ini, he la e sampled o he i s ime in his s udy; (3) we analyzed a sample popula ion om Luce a (Sou he n I aly) o he i s ime, a popula ion ha acco ding o documen a ion ecei ed an impo - an inpu o No h A ican immig an s du ing he hi een h cen u y; (4) we analyzed he pa e ns o m DNA a ia ion in I aly globally, ha is, by combining mo e han 3,700 con ol egion p o iles om he li e a u e (41 popula ion samples in o al) coupled wi h he mo e han 580 new p o iles p o ided he e; (5) Y- ch omosome haplo ype and haplog oup pa e ns a e analyzed in Pa e ns o m DNA Va ia ion in I aly PLOS ONE | www.plosone.o g 2 Decembe 2012 | Volume 7 | Issue 12 | e50794 pa allel wi h he m DNA da a in o de o de e mine he possible di e ences ha occu ed his o ically in he male e sus emale demog aphic mo emen s; and (6) he in lux o mig an s om A ica (No h and sub-Saha an) and o he egions is also analyzed using phylogeog aphic in e ences, and also a model o admix u e based on haplo ypic da a and a panel o ances y in o ma i e ma ke s (AIMs). Ma e ials and Me hods E hics s a emen W i en in o med consen was ob ained om all sample dono s. Analysis o m DNA sequences was app o ed by he ins i u ional e iew boa ds o he Uni e si a` Ca olica del Sac o Cuo e (Roma). Mo eo e , he s udy con o ms o he Spanish Law o Biomedical Resea ch (Law 14/2007- 3 o July). Samples A o al o 583 indi iduals we e sampled om along he I alian Peninsula, ep esen ing 12 di e en popula ions (Figu e 1), wo o hem (Ladin and G ecani Salen ini) being linguis ic isola es, and he Luce a being a his o ical encla e o A abs coming om No h A ica. A b ie desc ip ion o hese la e h ee popula ions is gi en below. In he I alian e i o y, he Alpine a c ep esen s one o he main a eas o p esence o alloglo popula ions, some o hem biologically isola ed o his o ical and geog aphic easons [27]. A he end o he medie al pe iod (,1200 AD) and especially in he alley zone, a i s coloniza ion o na i e peasan s began, s a ing wi h he use o lands p e iously exploi ed only o pas u e and he lumbe . Successi ely, wi h di e en modali ies and unde he con ol o laic and ecclesias ical owne s, he coloniza ion p ocess in ol ed mig an nuclei om he Ty ol, Ca in hian a ea and o he zones [28]. Cu en ly, he Alpine a c popula ions a e di e en ia ed wi h a ema kable cul u al di e si y ha is well ep esen ed by linguis ic elemen s. Thus, besides he o icial main languages, nume ous mino i y languages o dialec s a e also he cul u al pa imony o linguis ic mino i ies [27,29]. Ladin is o en a ibu ed o be a elic o ulga La in dialec s associa ed wi h Rhae o-Romance languages. In he as mul i-e hnic Holy Roman Empi e, and hen a e 1804 he Aus ian empi e, he Ladins we e le in ela i e peace and we e allowed o con inue he use o hei language and cul u e. G ecani Salen ini is a Hellenic-speaking linguis ic island o Salen o, si ua ed in sou he n Puglia, and consis ing o nine municipali ies in which a neo-G eek dialec , also known as G ecanic o G iko, is spoken. The o igins o his linguis ic island in Salen ine G eece a e unce ain. The Ge man linguis G. Rohl s p oposed i s o igin in he Magna G aecia egion; while O. Pa langeli sugges s a Byzan ine de i a ion o he G iki o Salen o. G eek esea che s (e.g. A. Ka anas asis) claim he inpu o Byzan ine elemen s in he p e-exis ing Magna G aecia ma ix. The G eek a i al in he Salen ine Peninsula occu ed bo h in he Magna G aecia, and pos e io Byzan ine domina ions. The nume ous illages o G ecani Salen ini had a G eek cul u e and language and p ac iced he G eek-o hodox eligion. In he beginning o he No man conques (ele en h cen u y), and mo e in ensi ely wi h he a i al o di e en casa i (clans) (S e ian, Angioin, A agones, e c), he ca holic cle gy supplan ed hose o he o hodox ai h [30]. The Luce a popula ion has ecei ed an impo an in lux om No h A ican A ab peoples (see [31]). Thus, a e he collapse o he Roman Empi e in Eu ope, he A ab domina ion sp ead in o he Medi e anean Basin. Re e ed o ei he as Moo s in Ibe ia o Sa acens in Sou he n I aly and Sicily, A abs a i ed in Eu ope in 711 AD, and in 831 AD Ibe ia and Sicily we e almos comple ely subjec ed o A ab domina ion [31]. In he hi een h cen u y, F ede ick II mo ed he Sicilian A abs o he ci y o Luce a (No h Apulia) [32]. This sample was geno yped o STRs and Y- ch omosome SNPs in Capelli e al. [31] To he bes o ou knowledge, all indi iduals collec ed in he p esen s udy we e no ma e nally and pa e nally closely ela ed; hey had di e en su names and all he dono s e e ed back a leas wo gene a ions in he egion whe e he samples we e collec ed. All he samples we e analyzed o he con ol egion and selec ed m SNPs (see below). A subse o he samples comp ised un ela ed males (n= 292) ep esen ing se en di e en popula ions. These samples we e geno yped o a panel o 17 Y-ch omosome SNPs (see below), and we e p e iously geno yped o he Y ile [33]. In addi ion, au osomal ances y in o ma i e ma ke s (AIMs) we e geno yped in 441 indi iduals (see below). DNA ex ac ion Blood ex ac ion was pe o med wi h a sal ing-ou me hod [34], modi ied and e-adap ed o buccal cells. Swabs we e incuba ed in 500 ml o 0.2 sodium ace a e, 35 ml o 10% SDS and 20 mlo 20 mg/ml P o einase K o 16 hou s a 56uC. They we e hen emo ed and 500 ml o 3 M NaCl solu ion was added. P o eins we e emo ed by cen i uga ion, and he DNA p ecipi a ed by adding 1 ml o e hanol 100% a 220uC o a ew hou s. A e cen i uga ion, he DNA pelle was wice washed wi h e hanol 70%, d ied and e-suspended in wa e . Fo he blood samples, aliquo s o 500 ml each we e hawed and ed cells selec i ely lysed by a 16lysis bu e . A e h ee washes wi h he lysis bu e , whi e cells we e pelle ed and he DNA ex ac ed using he sal ing-ou p o ocol. All he samples we e quan i ied by di ec compa ison wi h s anda d on aga ose 1% minigels (1 g o aga ose in 100 ml o TBE 1X- om he 1:10 dilui ion o TBE 10X). PCR and m DNA con ol egion sequencing M DNA has been sequenced o he comple e con ol egion, om posi ion 16024 (in HVS-I) o 569 (in HVS-II). The i s and second hype a iable egions (HVS-I/II) we e ampli ied ia he polyme ase chain eac ion (PCR) and using p ime s epo ed by A ´l a ez-Iglesias e al. [35]. PCR was ca ied ou in a 25 ml eac ion mix wi h 16 eac ion bu e (20 mM T is-HCl, ph 8.0, 0.1 mM EDTA, 1 mM DDT, 50% ( / ) glyce ol), 1.5 mM MgCl 2 , 200 mM each dNTP, 0.4 mM each p ime , 2.5 U (Uni s). Taq polyme ase and 0.1– 1 ng DNA empla e was added o he eac ion mix u e (Taq DNA Polyme ase, ecombinan . INVITROGENHCo po a ion). Am- pli ica ion was ca ied ou in a GENE AMPHPCR SYSTEM 9700 (Applied Biosys ems, Fos e Ci y, Cali o nia,U.S.A.) using a ho s a a 95uC o 1 min, ollowed by 36 cycles a 95uC o 30 sec, 55uC o 60 sec, and 72uC o 30 sec and a inal ex ension a 72uC o 15 min. Be o e he sequencing eac ion, PCR p oduc s we e checked by elec opho esis in polyac ylamide non-dena u - ing gel (T9, C5), and subsequen ly he gel was s ained wi h sil e ni a e. PCR p oduc s we e hen pu i ied wi h a Mul iSc eenH PCR m96 Pla e (Millipo e, Bed o d, Ma 01730, U.S.A), 96-well de ice.The acuum-based, size exclusion sepa a ion e ec i ely and quickly emo ed he con aining sal s, uninco po a ed dNTPs and p ime s om PCR eac ions. Cycle sequencing was pe o med on bo h s ands in a GENE AMPHPCR SYSTEM 9700 (AB) he mal cycle using he ABI P ismHdRhodamine Te mina o Cycle Sequencing Ready Reac ion Ki (AB). This ki consis s o a eac ion mix composed o : DNA-modi ied and Pa e ns o m DNA Va ia ion in I aly PLOS ONE | www.plosone.o g 3 Decembe 2012 | Volume 7 | Issue 12 | e50794 e mos able polyme ase, Bu e T is-HCl (pH 9.0), MgCl 2 , dNTPs, dichlo o hodamine-ma ked ddNTPs. An aliquo e o 30 ng amplicon and 3.2 M p ime s we e added o a 2 ml eac ion mix. Sequencing was ca ied ou using a ho s a a 96uC o 4 min, ollowed by 36 cycles a 96uC o 15 sec, 50uC o 10 sec, 60uC o 2 sec and a inal ex ension a 60uC o 10 min. The emo al o excess dideoxy e mina o s, p ime s and bu e was accomplished wi h an alcoholic pu i ica ion. The sequence p oduc s we e dena u ed wi h deionized o m- amide and analyzed by capilla y elec opho esis on an ABI PRISM 3130HGene ic Analyze (AB).The esul ing da a we e analyzed wi h PE/ABD so wa e Sequencing Analysis 5.2 and sequences we e aligned and compa ed wi h he Camb idge sequence [36] om posi ion 16024 o16569 o HVS-I and om posi ion 1 o 600 o HVS-II by he SeqScape .2.0 (AB). Analysis o m DNA coding egion SNPs Biallelic ma ke s we e geno yped using a mul iplex app oach [37]. The selec ed SNPs we e combined in o wo mul iplex eac ions. Mul iplex 1 included a selec ion o SNPs de ining common Eu opean haplog oups [38]. Mul iplex 2 included exclusi ely polymo phisms de ining sub-lineages inside hap- log oup H. P ime s we e designed in o de o adjus he annealing empe a u es and amplicon leng hs o allow analysis in mul iplex eac ions [37]. The sizes o he PCR p oduc s anged om 80 o 224 bp. Bo h mul iplexes we e pe o med using 10 ng o DNA empla e in a 25 ml eac ion olume comp ising 16Taq Gold Bu e (AB), 200 mM o each dNTP, 2 mM MgCl 2 and 0.5 U o AmpliTaq Gold Polyme ase (AB). Fo he p ime concen a ions, see [37]. Ampli ica ion was ca ied ou using a GENE AMPHPCR SYSTEM 9700 (AB) he mocycle . A e a 95uC p e-incuba ion s ep o 11 min, PCR was pe o med o a o al o 32 cycles using he ollowing condi ions: 94uC dena u a ion o 30 sec, annealing a 60uC o 30 sec and ex ension a 72uC o 1 min, ollowed by a 15 min inal ex ension a 72uC. PCR p oduc s we e checked by polyac ylamide gel elec opho esis (T9, C5) isualized by sil e s aining. A e ampli ica ion, PCR p oduc s equi ed pu i ica ion o emo e p ime s and uninco po a ed dNTPs. Pos -PCR pu i ica- ion was pe o med wi h ExoSapIT (Ame shan Pha macia Bio ech): 1 ml o PCR p oduc was incuba ed wi h 0.5 mlo Figu e 1. Map showing he loca ion o he samples analyzed in he p esen s udy and hose collec ed om he li e a u e (see Table 1). Pie cha s on he le display he dis ibu ion o m DNA haplog oup equencies, and hose on he igh he Y-ch omosome haplog oup equencies. doi:10.1371/jou nal.pone.0050794.g001 Pa e ns o m DNA Va ia ion in I aly PLOS ONE | www.plosone.o g 4 Decembe 2012 | Volume 7 | Issue 12 | e50794 ExoSapIT o 15 min a 37uC ollowed by 15 min a 80uC o enzyme inac i a ion. The minisequencing eac ion was pe o med in a GENE AMPHPCR SYSTEM 9700 (AB) he mocycle ollowing he ecommenda ions o he manu ac u e : 2 mlo SNaPsho eady eac ion mix, 0.2 mM o ex ension p ime o each SNP (see [37]) and 1 ml o bo h pu i ied PCR p oduc s in a o al olume o 7 ml. The eac ion mix u e was subjec ed o 25 single base ex ension cycles o dena u a ion a 96uC o 10 sec, annealing a 50uC o 5 sec and wi h an ex ension a 60uC du ing 30 sec. A e minisequencing eac ions, a pos -ex ension ea men o emo e he 59-phospho yl g oup o ddNTPs aided he p e en ion o co-mig a ion o uninco po a ed ddNTPs wi h ex ended p ime s and p oduc ion o a high backg ound signal. The inal olume (7 ml) was ea ed wi h 0.7 ml o SAP (Ame sham Biosciences) o 60 min a 37uC, ollowed by 15 min a 80uC o enzyme inac i a ion. The minisequencing p oduc s (1.5 ml) we e mixed wi h 10 mlo HiDi TM o mamide and 0.2 ml o GeneScan-120 LIZ size s anda d (AB) and elec o o esis was pe o med on an ABI PRISM 3130HGene ic Analyse (AB). The esul ing da a was analyzed wi h Gene Mappe ID. Minisequencing o SNPs cha ac e izing addi ional ypical Eu opean haplog oups Samples ha we e de e mined (using he SNP panel abo e) as being de i ed om J/T (T14766C; C7028T; T4216C), U (T14766C; C7028T; A12308G) and he U-subclade K (T14766C; C7028T; A12308G; A10398G), we e u he geno- yped using an addi ional se o 14 haplog oup-speci ic SNP ma ke s ha iden i y he ollowing sub-b anches: J1 (G3010A), J1b (G3010A; C13879T), J1c (G3010A; C114798T), J2 (G15257A), T2a (A14687G), T2b (G5147A), U5a (A14793G), U5a1 (A14793G; A15218G), U5b (A7768G), U5b1 (A7768G; A5656G), U5b2 (A7768G; C1721T), K1 (T14798C; T1189C), K1a (T14798C; T1189C; C0497T) and K2 (T14798C; T1189C; T9716C). PCR and minisequencing eac ions we e pe o med as desc ibed abo e. Fo PCR and minisequencing p ime concen- a ions, see Table S1. Geno yping o Y-SNPs Biallelic ma ke s we e geno yped using a mul iplex app oach [39]. A se o 30 SNPs was es ed, allowing assigna ion o he analyzed Y-ch omosome o haplog oups (Hg), ollowing he nomencla u e and he phylogene ic ela ionships de ined om he Y Ch omosome Conso ium [40]. The selec ed me hod o allele disc imina ion was a single base ex ension eac ion using he SNaPsho mul iplex ki (AB). We added he M269 ma ke o he i s o he ou mul iplexes, in o de be e o dissec he sub- haplog oup R1b (R1b3). The p ime s o his ma ke we e M269-F 59-TCA TGC CTA GCC TCA TTC CT-39and M269-R 59- TCT TTT GTG TGC CTT CTG AGG-39, and he minisequen- cing p ime 59-GGA ATG ATC AGG GTT TGG TTA AT-39. Geno yping o AIMs A panel o 52 AIMs we e geno yped acco ding o Sa´nchez e al. [41] in a subse o 441 indi iduals. Se e al o he popula ion da ase s we e used o in e -popula ion compa isons. This da a co esponded o he CEPH panel (h p://www.cephb. /en/ cephdb/) as epo ed in HapMap (h p://hapmap.ncbi.nlm.nih. go /) and was collec ed using he da a-mining ool SPSma [42,43]; i includes popula ion samples om all o e he wo ld (A ica, Eu ope, Asia, e c.); see legend o Figu e 2 o mo e in o ma ion. S a is ical analysis A o al o 42 I alian popula ion samples we e analyzed o m DNA in he p esen s udy. Compa a i e in e -popula ion analyses we e also ca ied ou o he HVS-I segmen anging om 16024 o 16365, since his is he analyzed segmen common o all o hem. Haplo ype (H) and nucleo ide di e si y (p) and o he di e si y indices [44–46] we e compu ed using DnaSP 4.10.3 so wa e [47]. P oblema ic a ia ion loca ed a ound 16189, usually associa ed o leng h he e oplasmy e.g. 16182C o 16183C, was igno ed. Analysis o molecula a iance (AMOVA) was ca ied ou using A lequin 3.5. [48]. Nomencla u e o m DNA lineages ollowed p e ious s udies e.g. [23,25,38,49,50]; see Phylo ee o a compila ion o he wo ldwide phylogeny and an upda e o he nomencla u e based on en i e m DNA genomes [51]. Geno yping and documen a ion e o s we e moni o ed ollowing he phylpogene ic p inciples p e iously applied e.g. [52– 59]. Mi ochond ial DNA and Y-ch omosome da a was collec ed om he li e a u e. The m DNA da a gene a ed in he p esen s udy was analyzed oge he wi h 3,834 m DNA HVS-I I alian p o iles collec ed om he li e a u e (Table S2; 76 sample popula ions). The Y-SNPs we e analyzed oge he wi h 1,251 I alian p o iles epo ed in he li e a u e (16 popula ion samples). A ull lis o e e ences o all he da a used in he p esen s udy is gi en in Table S2. Haplog oup equencies we e es ima ed by ch omosome coun ing. S a is ical di e ences in haplog oup equencies we e e alua ed using a Pea son’s chi- squa e es and by se ing up he nominal signi ican alue aas 0.05. Finally, classi ica ion o m DNA sequences in o haplog oups was pe o med ollowing phylogene ic c i e ia (Phylo ee Build 14, h p://www.phylo ee.o g/) and using bo h he con ol egion sequence p o ile and m SNPs. Resul s Molecula di e si y o m DNA and Y-ch omosome I alian p o iles Di e si y indices we e compu ed o all he popula ions analyzed in he p esen s udy and also in hose I alian popula ions samples epo ed in he li e a u e (Tables 1 and 2). Popula ion samples we e also g ouped in main egions (No h, Cen al, Sou h, Wes , and Eas ) in o de o in es iga e he ole o geog aphy in he dis ibu ion o m DNA a ia ion. Mi ochond ial DNA haplo ypes o he samples analyzed in he p esen s udy a e epo ed in Table S3.Table 1 shows he molecula di e si y alues based on m DNA da a o 41 I alian popula ion samples. The alues indica e ha he Isle o Elba is, by a , he I alian popula ion sample ha shows he lowes di e si y o all he indices compu ed, p obably as a consequence o i s ela i e isola ion om he coun y. I has been epo ed ha his was a well-known encla e o E uscan in luence, and some m DNA pa icula i ies ha e been desc ibed be o e [8,9]. Al e na- i ely, low molecula di e si y could be due o low sample sizes, al hough his ac is mi o ed in he s anda d de ia ion o he di e en es ima es. Excluding he Isle o Elba, haplo ype di e si y in I aly anges om 0.834 o 1, nucleo ide di e si y om 0.01003 o 0.02409, and he a e age alue o nucleo ide di e ences om 3.4 o 8.19 (a alue ha is co ela ed wi h he nucleo ide di e si y). In gene al, I aly shows some le el o he e ogenei y when examined o di e si y alues. When g ouping popula ions by main geog aphical egions, i can be obse ed ha Cen al I aly has sligh ly lowe alues han No h and Sou h I aly o all he indices compu ed (Table 1). The Pa e ns o m DNA Va ia ion in I aly PLOS ONE | www.plosone.o g 5 Decembe 2012 | Volume 7 | Issue 12 | e50794 highe di e si y alues we e ound in Sou h I aly. Di e si y alues a e howe e e y simila when examining popula ions loca ed in Wes I aly e sus hose in he Eas . The inclusion o Sicily (as pa o Sou h I aly) in he compu a ion does no subs an ially change hese es ima es (Table 1). Y-SNP da a we e ob ained o all he samples analyzed in he p esen s udy (Table S4). Table 2 shows he di e si y indices o he Y-SNPs in di e en I alian popula ions. The Y-STR di e si y alues o he samples analyzed in he p esen s udy and o he I alian and Eu opean samples ha e al eady been epo ed in B isighelli e al. [33]. As expec ed, di e si y alues o Y-SNP haplog oup pa e ns a e lowe han hose ob ained o he m DNA haplo ypes gi en ha he indices a e based on haplog oup and no on Y-STR haplo ypes. In ac , alues based on Y-STR p o iles (minimum o ex ended Y ile p o iles) [33] a e highe han hose obse ed o he HVS-I p o iles. Ladins a e among he popula ions wi h he lowes Y-SNP di e si y alues, while he G ecani Salen ini show di e si y alues ha a e compa able o o he I alian samples. Modena shows ema kable low haplo ype di e si y alues. Phylogeog aphy The m DNA haplog oup make-up o I aly as obse ed in ou samples i s well wi h expec a ions in a ypical Eu opean popula ion. Thus, mos o he I alian m DNAs (,89%) could be a ibu ed o Eu opean haplog oups H (,40%), I (,3%), J (,9%), T(,11%), U (,20%; U minus U6), V (,3%), X (,2%) and W (,1%); Figu e 1. The e a e howe e impo an di e ences in haplog oup equencies when examining hem by main geog aph- ical egions. Thus, o ins ance, haplog oup H is 59% in he No h, 46% in he Cen e , and decays o ,33% in he Sou h; mo eo e , hese egional di e ences a e s a is ically signi ican : No h s Sou h (Pea son’s chi-squa e, unadjus ed-P al- ue,0.00003), and Cen e s Sou h (Pea son’s chi-squa e, unad- jus ed-P alue,0.03724). Mi ochond ial DNA haplo ypes o A ican o igin a e mainly ep esen ed by haplog oups M1 (0.3%), U6 (0.8%) and L (1.2%); om he e onwa ds, L will be used o e e o all m DNA lineages, excluding he non-A ican b anches N and M [60,61]. A o al o 282 Y-ch omosomes we e analyzed o a se o Y- SNPs and we e classi ied in o 22 di e en haplog oups (Figu e 3). Two haplog oups we e no ound, e en hough ma ke s de ining hese clades we e es ed: N3 and R1a1. Fi e haplog oups ep esen ed 76.71% o he o al ch omosomes: R1b3, J2, I(xI1b2), E3b1 and G. The equencies a e aged ac oss popula- ions we e 26%, 21.2%, 10.2%, 9.9% and 9.2%, espec i ely. The emaining haplog oups sum o 23.2% in he o al sample, and ne e abo e 4% in single popula ion samples. R1b3 equency was ound o be highe in he no he n pa o he coun y, while he Y-ch omosome haplog oups G and E3b1, J2 and I(xI1b2) equencies we e highe in he sou h and in he cen al pa o he coun y, espec i ely (Figu e 1). Regional di e ences a e subs an ially highe in he Y-ch omo- some han in he m DNA. Thus, o ins ance, haplog oup R in he Y-ch omosome was 54% in he No h, 18% in he Cen e , and 31% in he Sou h. F equency di e ences we e s a is ically signi ican be ween No h s Cen e (Pea son’s chi-squa e, unadjus ed-P alue = 0.0014), and No h s Sou h (Pea son’s chi- Figu e 2. Analysis o AIMs in I alian popula ions e sus o he con inen al popula ion g oups. (A) PCA o I alian popula ions di ided in o he main egions No h, Cen e and Sou h (as analyzed in he p esen s udy) and o he Eu opean popula ions; (B) he same I alian popula ions plus sub-Saha an A ican, and Asian popula ions; (C) iangle plo as ob ained using STRUCTURE analysis o I alian, Eu opean, sub-Saha an, and Asian popula ions; (D) ba plo o ances al membe ship alues as ob ained using STRUCTURE analysis o he same popula ions used in (C). Popula ion codes: 1: Angola; 2: Kenya-Ban u NE; 3: Mozambique; 4: Namibia-San; 5: Nige ia-Yo uba; 6: Senegal-Mandenka; 7: Sou h A ica-Ban u; 8: Uganda; 9: B i ain; 10: Denma k; 11: F ench; 12: Ge many; 13: I eland; 14*: NW Spain; 15*: Po ugal; 16: Slo enia; 17: China-Dai; 18: China-Da u; 19: China-Han; 20: China-Hezhen; 21: Japanese; 22: Mongolia; 23: Taiwan; 24: Thailand. Geno ypes we e downloaded using he me hod in [43,83] and belong o he CEPH panel. An as e isk indica es Medi e anean popula ions. doi:10.1371/jou nal.pone.0050794.g002 Pa e ns o m DNA Va ia ion in I aly PLOS ONE | www.plosone.o g 6 Decembe 2012 | Volume 7 | Issue 12 | e50794 Table 1. Di e si y indices compu ed o di e en I alian egions based on HVS-I da a (sequence segmen 16090–16365). Popula ion Region Pop ID Re e ence N k k/n S h P M Ligu i NW 1 p.s. 50 40 0.8 53 0.96260.021 0.0142660.0145 4.875 To ino NW 5 [84] 50 45 0.9 49 0.99360.007 0.0148360.0011 5.056 Ladin NE 2, 13 p.s. [22,62,63,66] 504 170 0.3 106 0.96060.005 0.0125160.0004 4.252 Pa ia NE 6 [84] 47 35 0.7 44 0.96960.017 0.0131660.0012 4.502 Udine NE 3 p.s. 51 32 0.6 38 0.90360.038 0.0123160.0135 4.19858 A ezzo/Chiusi CW 1 [9] 14 14 1 22 1.00060.027 0.0148860.0129 5.088 Casen ino CW 15 [8] 122 77 0.6 167 0.97960.007 0.0240960.0082 8.190 Colle ecchio/Magliano Sabino CW 3 [9] 12 11 0.9 14 0.98560.040 0.0120160.0015 4.106 Elba CW 2 [9] 16 6 0.4 11 0.68360.120 0.0085360.0017 2.908 Fi enze CW 9 [84] 48 40 0.8 54 0.98060.014 0.0133260.0012 4.556 Jenne CW 22 [85] 103 34 0.3 47 0.83460.036 0.0100660.0360 3.440 La ini CW 5 p.s. 48 29 0.6 35 0.90260.039 0.0100360.0010 3.429 La ium CW 20 [86] 52 37 0.7 48 0.95960.019 0.0131360.0014 4.492 Mu lo CW 16 [8] 86 60 0.7 68 0.97660.010 0.0132760.0009 4.524 Roma CW 12 [84] 58 49 0.8 55 0.98760.008 0.0143360.0011 4.901 Te ni CW 11 [84] 29 20 0.7 33 0.94160.034 0.0120160.0014 4.108 Tuscany CW 4 [9,10,87] 127 86 0.7 77 0.98260.007 0.0130560.0075 4.464 Vallepie a CW 21 [85] 21 8 0.4 17 0.87160.044 0.0128160.0014 4.381 Vol e a CW 14 [8] 114 57 0.5 62 0.95560.013 0.0119360.0007 4.057 Ab uzzo CE 17 [86,88] 61 53 0.8 62 0.99060.007 0.0150060.0010 5.131 Ancona CE 10 [84] 73 55 0.7 59 0.96360.017 0.0137960.0010 4.717 Bologna CE 7 [84,89] 146 79 0.5 64 0.97060.008 0.0125060.0006 4.278 Cen e Eas CE 23 [90] 83 62 0.7 60 0.97460.012 0.0135260.0009 4.625 C oa ian I alians CE 19 [86] 41 28 0.7 46 0.97060.015 0.0152460.0017 5.213 Modena CE 8 [84] 44 33 0.7 43 0.95860.023 0.0113960.0012 3.895 Molise CE 18 [86] 62 41 0.6 58 0.93860.025 0.0126060.0013 4.309 Piceni CE 4 p.s. 53 43 0.8 56 0.98560.009 0.0130660.0011 4.414 Bel ede e SW 10 p.s. 50 41 0.8 44 0.98060.013 0.0132060.0010 4.532 Calab ia SW 27 [91,92] 389 213 0.5 128 0.98360.003 0.0152160.0004 5.203 Campania SW 30 [86] 48 41 0.8 59 0.98060.014 0.0151960.0014 5.166 Ca ania SW 11 p.s. 40 35 0.9 45 0.99060.010 0.0146060.0012 4.979 Sicily SW 28 [38,93–96] 558 240 0.4 125 0.95860.006 0.0128960.0004 4.343 T apani SW 12 p.s. 40 30 0.7 36 0.97760.013 0.0131360.0013 4.465 Apulia SE 26 [86] 26 24 0.9 43 0.99160.015 0.0155060.0022 5.304 Basilica a SE 25 [91] 92 65 0.7 70 0.98360.007 0.0129060.0008 4.428 G ecani Salen ini SE 8 p.s. 47 37 0.8 44 0.98960.007 0.0131060.0011 4.480 Luce a SE 6 p.s. 60 42 0.7 55 0.97660.011 0.0134560.0011 4.586 Sou h Apulia SE 9 p.s. 53 38 0.7 49 0.97360.014 0.0157960.0010 5.401 Sanni i SE 7 p.s. 50 41 0.8 49 0.98860.008 0.0142060.0013 4.843 Sa dinia – 29 [38,87,97] 351 171 0.4 98 0.95060.009 0.0118360.0004 4.033 Geog aphical egion No h I aly – – 702 267 0.4 126 0.96360.004 0.0128260.0004 4.295 Cen al I aly – – 1413 500 0.4 216 0.95860.004 0.0124360.0002 4.113 Sou h I aly – – 1453 569 0.4 183 0.97360.002 0.0136860.0002 4.541 Wes I aly (wi hou Sicily) – – 1437 578 0.4 232 0.96960.003 0.0131560.0002 4.405 Wes I aly (wi h Sicily) – – 2075 709 0.3 236 0.96360.003 0.0126060.0002 4.133 Eas I aly – – 1493 520 0.3 165 0.96460.003 0.0127760.0002 4.200 NW = No h-Wes ; NE = No h-Eas ; CW = Cen e -Wes ; CE = Cen e -Eas ; SW = Sou h-Wes ; SE = Sou h-Eas ; N= sample size; k = numbe o di e en haplo ypes; S = seg ega ing si es; h = haplo ype di e si y; p= nucleo ide di e si y; M = a e age numbe o nucleo ide di e ences. doi:10.1371/jou nal.pone.0050794. 001 Pa e ns o m DNA Va ia ion in I aly PLOS ONE | www.plosone.o g 7 Decembe 2012 | Volume 7 | Issue 12 | e50794 squa e, unadjus ed-P alue,0.00004). Haplog oup J2 also e- ealed impo an egional di e ences; i added o 9% in he No h, 37% in he Cen e , and 22% in he Sou h, wi h s a is ically signi ican di e ences be ween he No h s Cen e (Pea son’s chi- squa e, unadjus ed-P alue,0.00002), No h s Sou h (Pea son’s chi-squa e, unadjus ed-P alue,0.00148), and in he limi o signi icance Cen e s Sou h (Pea son’s chi-squa e, unadjus ed-P alue,0.049). Au osomal ances y in I aly A panel o 52 AIMs was geno yped in 435 I alian indi iduals in o de o es ima e he p opo ion o ances y om a h ee-way di e en ia ion: sub-Saha an A ica, Eu ope and Asia. S uc u e analyses allowed us o in e membe ship p opo ions in popula ion samples, and hese p opo ions can be g aphically displayed, as in Figu e 2. This analysis indica ed ha I alians ha e a basal p opo ion o sub-Saha an ances y ha is highe (9.2%, on a e age) han o he cen al o no he n Eu opean popula ions (1.5%, on a e age). The amoun o A ican ances y in I alians is howe e mo e compa able o (bu sligh ly highe han) he a e age in o he Medi e anean coun ies (7.1%). Figu e 2 shows in a iangle plo he ela ionships o I alians compa ed o o he Eu opean, A ican and Asian popula ions. PCA obse a ions con i med he esul s om S uc u e analysis, clus e ing I alian p o iles igh ly wi h o he Eu opean ones. Thus, PCA indica ed ha No h, Cen al and Sou h I aly do no show di e ences be ween hem, no om o he Eu opean popula ions (Figu e 2). PCA also indica ed clea -cu di e ences be ween I alians, A icans and Asians (Figu e 2). AMOVA AMOVA analyses we e ca ied ou ollowing di e en g ouping schemes. The samples we e pooled in o a single popula ion, bu also by conside ing main I alian egions. Analyses we e ca ied ou o e haplog oups and haplo ypes o he Y-ch omosome and he m DNA (Table 3). AMOVA indica ed ha , among popula ions, a iance was mo e s ongly s a i ied o he Y-ch omosome han o he Table 2. Di e si y indices compu ed o di e en I alian egions based on Y-SNPs. Popula ion Region Re e ence N k k/n Gene Di e si y Ligu ia NW P esen s udy 46 9 0.19 0.766260.0502 Ladin NE [14] 34 6 0.17 0.534860.0979 Udine NE P esen s udy 47 10 0.21 0.776160.0441 Cen al Tuscany CW [14] 40 8 0.20 0.739760.0616 Elba Island CW [14] 94 7 0.07 0.674260.0445 La ini CW P esen s udy 44 11 0.25 0.825660.0395 La ium CW [14] 43 9 0.20 0.802660.0388 Tuscany-La ium bo de CW [14] 76 7 0.09 0.755460.0350 Cen al Ma che CE [14] 59 7 0.11 0.729460.0364 Ma che CE [11] 162 13 0.08 0.848960.0152 Ma che-Appennine CE [14] 25 7 0.28 0.803360.0514 Modena CE [98] 62 8 0.12 0.532060.0743 Piceni CE P esen s udy 38 9 0.23 0.820860.0450 Rimini-Val Ma ecchia CE [99] 163 12 0.35 0.699060.0308 Bel ede e SW P esen s udy 27 9 0.33 0.854760.0477 Eas Campania SW [14] 46 7 0.15 0.687060.0618 Sicily SW P esen s udy 57 12 0.21 0.832760.0311 Wes Campania SW [14] 80 10 0.12 0.844660.0224 Wes Calab ia SW [14] 57 7 0.12 0.752560.0307 Sanni i SE P esen s udy 30 10 0.33 0.864460.0409 G ecani Salen ini SE P esen s udy 47 7 0.14 0.812260.0242 Luce a SE [31] 60 9 0.15 0.836560.0236 Sou h Apulia SE [14] 49 9 0.18 0.852960.0237 Sa dinia [100] 336 14 0.04 0.809860.0136 Geog aphical egion No h I aly – – 127 14 0.11 0.840060.0189 Cen al I aly – – 806 21 0.03 0.887060.0053 Sou h I aly – – 453 20 0.04 0.890960.0060 Wes I aly (wi hou Sicily) – – 553 17 0.03 0.856760.0094 Wes I aly (wi h Sicily) – – 610 20 0.03 0.870560.0078 Eas I aly – – 776 22 0.02 0.903460.0037 Codes a e as in Table 1. doi:10.1371/jou nal.pone.0050794. 002 Pa e ns o m DNA Va ia ion in I aly PLOS ONE | www.plosone.o g 8 Decembe 2012 | Volume 7 | Issue 12 | e50794 m DNA; he di e ence was much mo e ma ked o he analysis based on haplog oups (14.39% s 1.17%) han o he analysis based on haplo ypes (2.34% s 0.79%). Among popula ion a iance was e y low when analyzing main geog aphical egions; howe e , i was he la i ude (No h s Cen e s Sou h) ha appea ed o accoun o highe alues o among-popula ion a iance a he han longi ude (Wes s Eas ), wi h he excep ion o he Y-ch omosome haplog oups (al hough he alues a e below 1%); Table 3. Again, he Y-ch omosome showed sligh ly highe alues o among-popula ion a iance han did he m DNA. Fo he Y-ch omosome, a signi ican p opo ion o he wi hin- popula ion a iance mo ed o among-popula ion wi hin-g oups a iance, p obably due o he ac ha all popula ion samples had a e y high p opo ion o single on Y ile haplo ypes, ele a ing he maximum alues o haplog oup di e si y o all o hem [33]. Linguis ic isola es: Ladin and G ecani Salen ini Two linguis ic isola es a e ep esen ed in he samples analyzed in he p esen s udy: he Ladin and he G ecani Salen ini. O he popula ion samples o he Ladin ha e al eady been analyzed in he li e a u e [22,62,63]. We he e sampled 41 new Figu e 3. Phylogeny o Y-ch omosome SNPs and haplog oup equencies in di e en I alian popula ions. doi:10.1371/jou nal.pone.0050794.g003 Table 3. AMOVA analysis o main I alian egions (Pe mu a ions: 20000; P- alue,0.0000) o he m DNA con ol egion da a and he Y-ch omosome STRs and SNPs. All popula ions (%) No h s Cen e s Sou h (%) Wes s Eas (%) HAPLOTYPES m DNA (48 popula ions) Among pops 0.79 0 0 Wi hin pops 99.21 99.25 99.21 Among pops wi hin g oups – 0.75 0.79 Y-ch omosome (15 popula ions) Among pops 2.34 1.18 0 Wi hin pops 97.66 97.32 97.85 Among pops wi hin g oups – 1.50 2.15 HAPLOGROUPS m DNA (19 popula ions) Among pops 1.17 0.36 0 Wi hin pops 98.83 98.72 98.83 Among pops wi hin g oups – 0.92 1.17 Y-ch omosome (24 popula ions) Among pops 13.92 0.07 0.83 Wi hin pops 86.08 86.06 85.74 Among pops wi hin g oups – 13.87 13.44 Sa dinians we e no included in he analysis. Re e ences o popula ion samples a e gi en in Table S2. doi:10.1371/jou nal.pone.0050794. 003 Pa e ns o m DNA Va ia ion in I aly PLOS ONE | www.plosone.o g 9 Decembe 2012 | Volume 7 | Issue 12 | e50794