Blood samples (212 in total) from unrelated individuals from the following three ethnic groups: Abkhazians (98), Georgians (Mingrelians) (72), Armenians (42) were collected in the Abkhazian Republic after informed consent was obtained from all participants. The origin of all subjects participating in this study was ascertained over three generations. Published data for additional ethnic groups has been taken for comparison in this study (Table 1).

      DNA samples were extracted from peripheral blood lymphocytes using a phenol-chloroform extraction method [10]. All the samples were genotyped for eight Alu insertion markers (ACE, ApoA1, pv92, TPA25, Ya5NBC27, Ya5NBC102, Ya5NBC148, Ya5NBC182). Primer sequences have been described previously [11].

      Allele frequencies and heterozygosity were determined by direct counting. A principal component analysis made use of the Statistica 6.0 package. The Gst value (the coefficient of gene differentiation) has been calculated as described by Nei and Chesser [13]. The Hardy-Weinberg equilibrium was evaluated by an exact test [14].