In a worldwide collaborative effort, 19,630 Y-chromosomes were sampled from 129 different populations in 51 countries. These chromosomes were typed for 23 short-tandem repeat (STR) loci (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385ab, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635, GATAH4, DYS481, DYS533, DYS549, DYS570, DYS576, and DYS643) and using the PowerPlex Y23 System (PPY23, Promega Corporation, Madison, WI). Locus-specific allelic spectra of these markers were determined and a consistently high level of allelic diversity was observed. A considerable number of null, duplicate and off-ladder alleles were revealed. Standard single-locus and haplotype-based parameters were calculated and compared between subsets of Y-STR markers established for forensic casework. The PPY23 marker set provides substantially stronger discriminatory power than other available kits but at the same time reveals the same general patterns of population structure as other marker sets. A strong correlation was observed between the number of Y-STRs included in a marker set and some of the forensic parameters under study. Interestingly a weak but consistent trend toward smaller genetic distances resulting from larger numbers of markers became apparent.

A collaborative work was carried out by the Spanish and Portuguese ISFG Working Group (GEP-ISFG) to estimate Y-STR mutation rates. Seventeen Y chromosome STR loci (DYS19, DYS385, DYS389I and II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439, DYS460, DYS461, DYS635 [GATA C4], GATA H4, and GATA A10) were analyzed in a sample of 3,026 father/son pairs. Among 27,029 allele transfers, 54 mutations were observed, with an overall mutation rate across the 17 loci of 1.998 x 10(-3) (95% CI, 1.501 x 10(-3) to 2.606 x 10(-3)). With just one exception, all of the mutations were single-step, and they were observed only once per gametogenesis. Repeat gains were more frequent than losses, longer alleles were found to be more mutable, and the mutation rate seemed to increase with the father's age. Hum Mutat 26(6), 520-528, 2005. (c) 2005 Wiley-Liss, Inc.

No abstract

Autosomal STRs, Y-chromosome markers, and mitochondrial DNA sequences were investigated in six Mbyá-Guaraní villages (Fortín M'Bororé, Yryapu, Tabay, Kaaguy Poty, Jejy, and Yaboti), all of them settled within the province of Misiones, northeastern Argentina. One hundred twenty-one unrelated individuals were analyzed. The study involved typing fifteen autosomal STRs, nine Y-chromosome STRs, and four biallele loci in the nonrecombinant region of the Y chromosome, sequencing the mtDNA of hypervariable regions I and II, and detecting the 9-bp ins/del in region V of mtDNA. All autosomal STRs were in Hardy-Weinberg equilibrium. The four major native American mtDNA haplogroups were represented in the sample. Haplogroups A2 and D1 exhibited the highest frequencies (40.5% and 36.0%, respectively), and haplogroups B2 and C1 appeared to be less frequent (17.5% and 6.0%, respectively). The native American haplogroup Q1a3a was observed in a relevant proportion (88.8%). In addition, a nine-STR Y-chromosome haplo-type (DYS19*13, DYS389I*14, DYS389II*31, DYS390*24, DYS391*11, DYS392*14, DYS393*11, DYS385A*14, DYS385B*16) exhibited a frequency of more than 36%. Our results indicate that the analyzed Argentinean Guaraní individuals are genetically more closely related to Guaraní from Brazil [genetic distance (Δµ)(2) = 0.48] than to other related tribes that are geographically closer. Statistical approaches based on autosomal data do not support the hypothesis of genetic drift previously proposed; however, this apparent discrepancy might be due to the lack of sensitivity of the autosomal markers used here.

No abstract

No abstract

No abstract

No abstract