title: Uniparental markers in Italy reveal a sex-biased genetic structure and different historical strata.
abstract: Located in the center of the Mediterranean landscape and with an extensive coastal line, the territory of what is today Italy has played an important role in the history of human settlements and movements of Southern Europe and the Mediterranean Basin. Populated since Paleolithic times, the complexity of human movements during the Neolithic, the Metal Ages and the most recent history of the two last millennia (involving the overlapping of different cultural and demic strata) has shaped the pattern of the modern Italian genetic structure. With the aim of disentangling this pattern and understanding which processes more importantly shaped the distribution of diversity, we have analyzed the uniparentally-inherited markers in ∼900 individuals from an extensive sampling across the Italian peninsula, Sardinia and Sicily. Spatial PCAs and DAPCs revealed a sex-biased pattern indicating different demographic histories for males and females. Besides the genetic outlier position of Sardinians, a North West-South East Y-chromosome structure is found in continental Italy. Such structure is in agreement with recent archeological syntheses indicating two independent and parallel processes of Neolithisation. In addition, date estimates pinpoint the importance of the cultural and demographic events during the late Neolithic and Metal Ages. On the other hand, mitochondrial diversity is distributed more homogeneously in agreement with older population events that might be related to the presence of an Italian Refugium during the last glacial period in Europe.
authors.affiliation: Laboratorio di Antropologia Molecolare, Dipartimento di Scienze Biologiche, Geologiche e Ambientali, Università di Bologna, Bologna, Italy.
authors.forename: Alessio
authors.initials: A
authors.lastname: Boattini
authors.forename: Begoña
authors.initials: B
authors.lastname: Martinez-Cruz
authors.forename: Stefania
authors.initials: S
authors.lastname: Sarno
authors.forename: Christine
authors.initials: C
authors.lastname: Harmant
authors.forename: Antonella
authors.initials: A
authors.lastname: Useli
authors.forename: Paula
authors.initials: P
authors.lastname: Sanz
authors.forename: Daniele
authors.initials: D
authors.lastname: Yang-Yao
authors.forename: Jeremy
authors.initials: J
authors.lastname: Manry
authors.forename: Graziella
authors.initials: G
authors.lastname: Ciani
authors.forename: Donata
authors.initials: D
authors.lastname: Luiselli
authors.forename: Lluis
authors.initials: L
authors.lastname: Quintana-Murci
authors.forename: David
authors.initials: D
authors.lastname: Comas
authors.forename: Davide
authors.initials: D
authors.lastname: Pettener
mesh_terms: D041322:Chromosomes, Human, Y / Q000145:classification / Q000235:genetics*; D016000:Cluster Analysis; D004272:DNA, Mitochondrial / Q000145:classification / Q000235:genetics*; D005260:Female; D014644:Genetic Variation; D005828:Genetics, Population / Q000379:methods*; D005843:Geography; D006239:Haplotypes / Q000235:genetics; D006801:Humans; D007558:Italy; D008297:Male; D010802:Phylogeny; D025341:Principal Component Analysis; D013997:Time Factors
chemical_list: D004272:DNA, Mitochondrial