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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2006.05.002 Byline: A.M. Cadenas (a), M. Regueiro (a), T. Gayden (a), N. Singh (b), L.A. Zhivotovsky (c), P.A. Underhill (d), R.J. Herrera (a) Keywords: Amelogenin; Deletion; Y-SNP; Y-STR; Forensic Abstract: Several commercial PCR multiplex kits incorporate the amelogenin locus for the purpose of human gender identification. Consequently, erroneous results in the electropherogram profile of this locus can carry important forensic implications. In this study, dropout of the amelogenin Y allele was detected in 5 out of 77 phenotypically normal Kathmandu males using the AmpFlSTR.sup.[R] Identifiler.sup.[R] kit. A battery of male-specific markers including SNPs, STRs, STSs, and a minisatellite were amplified for the five amelogenin null samples in order to delineate the breakpoints of the deletions as well as assess the overall integrity of the Y-chromosome. This study represents the first to examine the haplogroup affiliation of the AMGY deletions. The analyses performed suggest a single origin for the five deletions as indicated by their allocation to a specific Y-haplogroup (J2b2-M241), related Y-STR haplotypes and identical regional localization of breakpoints. The age estimated from the microsatellite variation for the amelogenin deletions (if they are associated by descent) is approximately 6.5[+ or -]3.3ky, younger than the previously reported related age of the M241 haplogroup representatives (13-14ky). Our data in combination with previous publications suggest a concentration of afflicted individuals in the Indian subcontinent, possibly as a result of common ancestry. The elevated incidence of the amelogenin dropout in these populations accentuates the need to utilize other loci for gender determination in order to obtain an accurate set of inclusion criteria in forensic casework. Author Affiliation: (a) Department of Biological Sciences, Florida International University, University Park, OE 304, Miami, FL 33199, USA (b) Faculty of Medicine, Henan University, Kaifeng, Henan, China (c) N.I. Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, Russia (d) Department of Genetics, Stanford University, Stanford, USA Article History: Received 1 March 2006; Revised 3 April 2006; Accepted 7 May 2006

An informative set of biallelic polymorphisms was used to study the structure of Y-chromosome variability in a sample from the Mediterranean islands of Corsica and Sicily, and compared with data on Sardinia to gain insights into the ethnogenesis of these island populations. The results were interpreted in a broader Mediterranean context by including in the analysis neighboring populations previously studied with the same methodology. All samples studied were enclosed in the comparable spectrum of European Y-chromosome variability. Pronounced differences were observed between the islands as well as in the percentages of haplotypes previously shown to have distinctive patterns of continental phylogeography. Approximately 60% of the Sicilian haplotypes are also prevalent in Southern Italy and Greece. Conversely, the Corsican sample had elevated levels of alternative haplotypes common in Northern Italy. Sardinia showed a haplotype ratio similar to that observed in Corsica, but with a remarkable difference in the presence of a lineage defined by marker M26, which approaches 35% in Sardinia but seems absent in Corsica. Although geographically adjacent, the data suggest different colonization histories and a minimal amount of recent gene flow between them. Our results identify possible ancestral continental sources of the various island populations and underscore the influence of founder effect and genetic drill The Y-chromosome data are consistent with comparable mtDNA data at the RFLP haplogroup level of resolution, as well as linguistic and historic knowledge. KEY WORDS Y-chromosome; population genetics; Mediterranean populations

Whether East Asians were involved in the earliest migrations to the New World remains unclear. In this study, more than 3,000 Y chromosomes from East Asia, Siberia and America were analyzed using Y chromosome specific biallelic and microsatellite markers. Our results showed that the RPS4Y711T, an Asian specific allele, has a wide distribution in East Asia, and reaches to the highest frequency in the Northern Asian populations. The gene diversity of the RPS4Y711Ts in East Asians, based on microsatellites, is four times higher than those in Siberians and American Indians suggesting a northward migration starting in East Asia. This northward migration is marked by a founder event in North Asian populations which are associated with the prevalence (88.8%) of a unique microsatellite allele, DYS391-9 in most of the North Asian RPS4Y711T Y chromosomes, which were originally derived from DYS391-10 alleles in East Asian populations. The founder effect was further reflected by restricted distribution of an A to G mutation at a Y chromosome locus M48 in Siberian populations. Hence, we propose that a prehistoric migration associated with the RPS4Y polymorphism started from the southern part of East Asia, crossing mainland China, reaching Siberia about 15,000 years ago and eventually contributed to the second migration wave to the New World.