1Anthropology and Forensic Science, George Washington University, Washington, DC, 2Armed Forces DNA Identification Laboratory, American Registry of Pathology, Camden, DE, 3Armed Forces DNA Identification Laboratory, Armed Forces Medical Examiner System, Dover, Air Force Base, 4Forensic Genetics, National Institute of Standards and Technology, Gaithersburg, MD, 5Department of Anthropology, University of Kansas, Lawrence, KS
Friday 5:00-5:15, 200ABC
A total of 535 chromosomes from US European (132), SW Hispanics (155), African Americans (118), West Africans (primarily Ghana and Nigeria)(30), Ethiopia (34), SE Asia (32) and Siberia (34) were tested for 15 X chromosome STR loci (DXS8378, DXS9902, DXS6795 [LG1], DXS7132, DXS6803, DXS6789, DXS7424, DXS101, GATA172D05, DXS7130, GATA165B12 [LG2], HPRTB [LG3], GATA31E08, DXS10147 and DXS7423 [LG4]), yielding 144 alleles using two multiplexes developed at AFDIL for forensic purposes. The loci were individually analyzed by FST analysis across the seven populations, and aggregately analyzed using PCA followed by hierarchical cluster analysis. All probability values were corrected for multiple tests using the Bonferroni correction.
The results of the FST analysis indicated that 11/15 loci had FST values >0.05, 9 of which were significant at the α= 0.05 level, however only 4/15 were significant after Bonferroni correction. PCA analysis yielded six Eigen vectors which accounted for 100% of the variance, and generated highly discriminating factor scores for the seven populations.
Cluster analysis using Ward’s Method on a Squared Euclidean distance matrix generated an anthropologically expected tree with African Americans clustering with West Africans on a deep root, East Asian and Europeans on a separate branch, with the Siberian and SE Asians separated by a relatively deep root as expected. An unexpected result was the Europeans and SW Hispanics (admixed) clustering, and the Ethiopians also clustering in this group indicating commonality with Europeans. These results support the use of these markers as tools in the investigation of the origins of modern human populations.
This research was supported by grants from the Columbian College of Arts and Science (GWU) and NIJ grant #2011-DN-BX-K401 Disclaimer: The opinions and assertions contained herein are solely those of the authors and are not to be construed as official views of the United States Department of Defense or the United States Department of the Army.