Analysis of human platelet antigen systems in a Moroccan Berber population

Abstract

The human platelet alloantigen systems HPA-1, -2, -3, -4, -5 and -6 in a Moroccan Berber population from the Amizmiz region were determined by polymerase chain reaction using sequence-specific primers (PCR-SSP). The gene frequencies obtained from these unrelated Berbers were 0 x 747 and 0 x 252 for HPA-1a and -1b; 0 x 817 and 0 x 182 for HPA-2a and -2b; 0 x 682 and 0 x 317 for HPA-3a and -3b; 1 and 0 x 0 for HPA-4a and -4b; 0 x 8616 and 0 x 1383 for HPA-5a and -5b; 1 and 0 x 0 for HPA-6a and -6b. The Berbers have the highest frequency for the 1b, 2b and 5b alleles of all the populations reported to date and also the lowest frequency for the 3b allele.

Gene frequencies of human platelet alloantigens in Bahraini Arabs

“…The prevalence of HPA-1b (24%) and HPA-2b (23%) were high among Bahrainis, compared with Africans [3], Asians [5,8], and Europeans [6], which was comparable to rates established for Saudi Arabia [9], Tunisia [10], and North African Berbers [7], suggesting that Arabian Peninsula-North Africa is focus of HPA-1b. The prevalence of HPA-3b (43%) was less selective, as prevalence rates among Bahrainis were comparable to Asians [5,8] and Europeans [6].…”

“…The distribution of HPA genotypes is geographically and ethnically restricted. The prevalence of HPA5b and HPA-2b is high among Africans [3] but very low among Asians [4,5], while the frequency of HPA-1b is higher among Caucasians [6] and Berbers [7] than Asians [4,5]. In so far as data on the distribution of HPA polymorphisms among Arabs are scanty, the present study investigated the diversity in HPA alleles, genotypes, and haplotypes in Bahrain, an island kingdom located in the Arabian Gulf.…”

Association of Human Platelet Alloantigen 1 through 5 Polymorphisms with Ischemic Stroke

“…HPA-1 (T196C, Leu33Pro), HPA-3 (T2622G, Ile843Ser), and HPA-4 (G526A, Arg143Glu) are present on the GPIIb/IIIa receptor complex [11], while HPA-2 (T524C, Met145Thr) is found on the von Willebrand Factor receptor GPIb/IX [12], and HPA-5 (G1648A, Glu505Lys) is on the collagen receptor GPIa/IIa [13]. The distribution of these gene variants is geographically and ethnically restricted, evidenced by the high prevalence of HPA-5b and HPA-2b among Africans [14], and their low frequencies among Asians [15,16,17], and the high frequency of HPA-1b among Caucasians [18] and Berbers [19], compared to Africans and Asians.…”

Human Platelet Antigens

“…31 Anti-HPA-1a antibodies inhibit clot retraction and platelet aggregation; in the latter case, presumably because they block the binding of fibrinogen. 33 36 Asian, 36,190,204,205,[207][208][209][210][211][212][213]215 Central African, 36 North African, 36,216 black American, [188][189][190]203 Amerindian, 188,189,218 Native American, 220 Amerindian (3) Aboriginal (2) Asian (12) Figure 9-3 HPA-3b frequencies among selected racial/ethnic populations. The frequencies of HPA-3b (abscissa) among the populations listed on the ordinate are depicted.…”

“…Each data entry (bar) represents the mean and standard deviation for the number of studies indicated in parentheses. References: White, 36,[188][189][190][191][192][193][194][195][196][197][198][199][200][201][202][203]220 Southeast Asian, 36 Asian, 36,189,190,204,205,[207][208][209][210][211][212][213]215 Central African, 36 North African, 36,216,217 black American, [188][189][190]203,220 Amerindian, 188,189,218 Native American, 220 and Aboriginal. 202,219…”