ABSTRACT
We have analyzed mtDNA HVI sequences and Y chromosome haplogroups based on 11 binary markers in 371 individuals, from 11 populations in the Caucasus and the neighbouring countries of Turkey and Iran. Y chromosome haplogroup diversity in the Caucasus was almost as high as in Central Asia and the Near East, and significantly higher than in Europe. More than 27% of the variance in Y-haplogroups can be attributed to differences between populations, whereas mtDNA showed much lower heterogeneity between populations (less then 5%), suggesting a strong influence of patrilocal social structure. Several groups from the highland region of the Caucasus exhibited low diversity and high differentiation for either or both genetic systems, reflecting enhanced genetic drift in these small, isolated populations. Overall, the Caucasus groups showed greater similarity with West Asian than with European groups for both genetic systems, although this similarity was much more pronounced for the Y chromosome than for mtDNA, suggesting that male-mediated migrations from West Asia have influenced the genetic structure of Caucasus populations.
Subject(s)
Chromosomes, Human, Y/genetics , DNA, Mitochondrial/genetics , Genetic Variation , White People/genetics , Ethnicity , Genetics, Population , Haplotypes , Humans , Male , Tandem Repeat SequencesABSTRACT
We have analyzed the beta-thalassemia mutations in 99 chromosomes of 49 adults with beta-thalassemia major and of one with Hb S-beta-thalassemia, who are regular patients at a large hematology clinic in Bakü, Azerbaijan. A total of 20 different mutants were identified; three [frameshift at codon 8 (-AA); IVS-II-I (G-->A); IVS-I-110 (G-->A)] were present in about two-thirds of all chromosomes. Most alleles are the same as found in Mediterranean populations; a few have an Asian origin or come from Kurdistan, Lebanon, Saudi Arabia, or a black population. One mutant [frameshift at codons 82/83 (-G)] might be specific for the Azerbaijanian population. Nearly all patients were transfused, which made quantitation of Hb F impossible; high G gamma values were present in the Hb F of those patients whose beta-thalassemia chromosome carried the C-->T mutation at position -158 in the promoter of the G gamma-globin gene.