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

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.