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DMXX
06-23-2014, 12:12 AM
Analysis of 22 Y chromosomal STR haplotypes and Y haplogroup distribution in Pathans of Pakistan.
Lee EY, Shin KJ, Rakha A, Sim JE, Park MJ, Kim NY et al. - Forensic Sci Int Genet. 2014 Jul;11:111-6. doi: 10.1016/j.fsigen.2014.03.004. Epub 2014 Mar 15.



We analyzed haplotypes for 22 Y chromosomal STRs (Y-STRs), including 17 Yfiler loci (DYS19, DYS385a/b, DYS389I/II, DYS390, DYS391, DYS392, DYS393, DYS437, DY438, DYS439, DYS448, DYS456, DYS458, DYS635 and Y-GATA-H4) and five additional STRs (DYS388, DYS446, DYS447, DYS449 and DYS464), and Y chromosomal haplogroup distribution in 270 unrelated individuals from the Pathans residing in the Federally Administered Tribal Areas and the North-West Frontier Province of Pakistan using in-house multiplex PCR systems. Each Y-STR showed diversities ranging from 0.2506 to 0.8538, and the discriminatory capacity (DC) was 73.7% with 199 observed haplotypes using 17 Yfiler loci. By the addition of 5 Y-STRs to the Yfiler system, the DC was increased to 85.2% while showing 230 observed haplotypes. Among the additional 5 Y-STRs, DYS446, DYS447 and DYS449 were major contributors to enhancing discrimination. In the analysis of molecular variance, the Pathans of this study showed significant differences from other Pathan populations as well as neighboring population sets. In Y-SNP analysis, a total of 12 Y chromosomal haplogroups were observed and the most frequent haplogroup was R1a1a with 49.3% frequency. To obtain insights on the origin of Pathans, the network analysis was performed for the haplogroups G and Q observed from the Pathans and the Jewish population groups including Ashkenazim and Sephardim, but little support for a Jewish origin could be found. In the present study, we report Y-STR population data in Pathans of Pakistan, and we emphasize the need for adding additional markers to the commonly used 17 Yfiler loci to achieve more improved discriminatory capacity in a population with low genetic diversity.


[Link (http://www.ncbi.nlm.nih.gov/pubmed/24709582)]

The authors found Y-DNA R1a1a-M17 at a frequency less than the ballpark range established by previous papers. There are two more interesting aspects of this study, however:

1) The 17 STRs comprising the Y-Filer system (commonly used commercial kit) was approximately an eighth less discriminatory than their custom 22 STR panel. If future studies are to benefit from this paper's finding, a more expansive STR array should be used and Y-Filer alone should not be deemed sufficient when it comes to interpreting Y-STR data. This has immediate repercussions with respect to the current body of data we have, given countless studies have used the Y-Filer system. In my opinion, this relegates datasets consisting of Y-Filer data as useful only in ascertaining matches with a GD<2-3.

2) The authors concluded Pakistani Pashtun Y-DNA Q and G have no discernible shared origin with the Jewish populations sampled. I am not intimately familiar with the variety of Y-DNA Q found among Pashtuns, but the Y-DNA G2c* that has consistently appeared in studies sampling the Pashtuns has been used as supporting evidence by various individuals/groups for them having Israelite origins, be it partially or wholly. A direct inspection of the G haplotypes presented here would help us to discern whether, much like Pashtun R1a1a, it stems from a common recent founder. If that is the case, alternative recent origins beyond Israel would have to be sought.

Sein
06-23-2014, 02:55 AM
Analysis of 22 Y chromosomal STR haplotypes and Y haplogroup distribution in Pathans of Pakistan.
Lee EY, Shin KJ, Rakha A, Sim JE, Park MJ, Kim NY et al. - Forensic Sci Int Genet. 2014 Jul;11:111-6. doi: 10.1016/j.fsigen.2014.03.004. Epub 2014 Mar 15.



[Link (http://www.ncbi.nlm.nih.gov/pubmed/24709582)]

The authors found Y-DNA R1a1a-M17 at a frequency less than the ballpark range established by previous papers. There are two more interesting aspects of this study, however:

1) The 17 STRs comprising the Y-Filer system (commonly used commercial kit) was approximately an eighth less discriminatory than their custom 22 STR panel. If future studies are to benefit from this paper's finding, a more expansive STR array should be used and Y-Filer alone should not be deemed sufficient when it comes to interpreting Y-STR data. This has immediate repercussions with respect to the current body of data we have, given countless studies have used the Y-Filer system. In my opinion, this relegates datasets consisting of Y-Filer data as useful only in ascertaining matches with a GD<2-3.

2) The authors concluded Pakistani Pashtun Y-DNA Q and G have no discernible shared origin with the Jewish populations sampled. I am not intimately familiar with the variety of Y-DNA Q found among Pashtuns, but the Y-DNA G2c* that has consistently appeared in studies sampling the Pashtuns has been used as supporting evidence by various individuals/groups for them having Israelite origins, be it partially or wholly. A direct inspection of the G haplotypes presented here would help us to discern whether, much like Pashtun R1a1a, it stems from a common recent founder. If that is the case, alternative recent origins beyond Israel would have to be sought.

Thanks for sharing this!

Have they listed Pashtun Y-HG frequencies for all 12 Y-HGs? Unfortunately, I don't have access to the paper. It seems very interesting, and the sample size is excellent.