Different Patterns of Variation at the X- and Y-Chromosome-Linked Microsatellite Loci DXYS156X and DXYS156Y in Human Populations

Document Type

Article

Authors

Tatiana Karafet, University of Arizona; Laboratory of Human Molecular and Evolutionary Genetics, Institute of Cytology and Genetics
Peter De Knijff, Leiden University
Elizabeth Wood, University of Arizona
Jared Ragland, University of Arizona
Andrew Clark, Pennsylvania State University
Michael F. Hammer, University of Arizona

Abstract

We compared the global pattern of variation at two homologous microsatellites mapping to the long arm of the X chromosome (DXYS156X) and to the short arm of the Y chromosome (DXYS156Y) in humans. A single pair of oligonucleotide primers amplifies these two nonallelic loci, each of which contains polymorphism in the number of pentanucleotide units. We observed 11 alleles in a sample of 2290 X chromosomes and 2006 Y chromosomes from 50 populations representing 6 major geographic regions. The overlapping size range of the Xand Y-chromosome alleles indicated a more complex distribution of alleles at these two loci than previously reported. Contrasting patterns of X-chromosome-linked and Y-chromosome-linked variation were reflected in statistically significant differences in genetic diversity values among geographic regions and between X and Y chromosomes. Higher levels of diversity characterized the DXYS156X locus in Africa (0.799 ± 0.004) and the DXYS156Y locus in East Asia (0.700 ± 0.006) compared with populations from other regions. These different patterns of variation can be explained by a combination of processes at both the molecular and population levels, including variable mutation rates, different effective population sizes, and genetic drift.

Recommended Citation

Karafet, Tatiana; De Knijff, Peter; Wood, Elizabeth; Ragland, Jared; Clark, Andrew; and Hammer, Michael F. (1998) "Different Patterns of Variation at the X- and Y-Chromosome-Linked Microsatellite Loci DXYS156X and DXYS156Y in Human Populations," Human Biology: Vol. 70: Iss. 6, Article 1.
Available at: https://digitalcommons.wayne.edu/humbiol/vol70/iss6/1