Genetic variation in a compound short tandem repeat/Alu haplotype system at the SB19.3 locus: Properties and interpretation

• Type: Article in International Scientific Journal
• Date: 2004

Authors

Gaspar, P (Author) Other; Seixas, S (Author) Other; Rocha, J (Author) FCUP

Journal

Title: Human Biology

Vol. 76

Pages: 277-287

ISSN: 0018-7143

Publisher: Wayne State University Press

Indexing

ISI Web of Knowledge - 2 Citations

Scopus - 1 Citation

Scientific classification

FOS: Natural sciences > Biological sciences

Other information

Authenticus ID: P-000-AZ0

DOI: 10.1353/hub.2004.0032

Abstract (EN): The genetic variation at a compound nonrecombining haplotype system, consisting of the previously reported SB19.3 Alu insertion polymorphism and a newly identified adjacent short tandem repeat (STR), was studied in population samples from Portugal and Sao Tome (Gulf of Guinea, West Africa). Age estimates based on the linked microsatellite variation suggest that the Ala insertion occurred about 190,000 years ago. In accordance with the global patterns of distribution of human genetic variation, the highest haplotype diversity was found in the African sample. This excess in African diversity was due to both a substantial reduction in heterozygosity at the Alu polymorphism and a lower STR variability associated with the predominant Alu insertion allele in the Portuguese sample. The high level of interpopulation differentiation observed at the Alu locus (F-ST = 0.43) was interpreted under alternative selective and demographic scenarios. The need for compatibility between patterns of variation at the STR and Alu loci could be used to restrict the range of selection coefficients in selection-driven genetic hitchhiking frameworks and to favor demographic scenarios dominated by larger pre-expansion African population sizes. Taken together, the data show that the SB 19.3 Alu-STR system is an informative marker that can be included in more extended batteries of compound haplotypes used in human evolutionary studies.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 11