Y chromosome J2 subtyping in an Italian sample: Population and forensic implications

In the recent years the Y chromosome genealogy has been refined by a number of newly discovered SNPs. The non-random distribution of the Y chromosome lineages worldwide makes fundamental the dissection and characterisation of haplogroups associated with specific geographic areas. In Southern Europe the haplogroup J2, as defined by the M172 marker, can reach frequencies up to 35%, making the dissection of such lineage critical for population studies. Here we present a study on J2 chromosomes from the Italian peninsula. Populations and forensic implications are discussed. A total of 900 individuals were previously genotyped for a number of SNPs, including M172. More than 200 of these have been now genotyped for 7 SNPs within the J2 lineage using a multiplex SNaPshot approach. The different distribution of the various lineages in different geographic areas probably reflects different historical demographic events and points to differential Y chromosome haplotype distribution, with implication for forensic application of this genetic marker.