HLA alleles and haplotypes in French North African immigrants.

Human leukocyte antigen (HLA) haplotypes (n = 187) were genotyped and assigned by the mode of inheritance in migrant families from North Africa who reside in the Paris, France, area. The distribution of alleles and haplotypes in that population was compared with the one obtained in a control population of ancient French natives residing in the same area (248 independent haplotypes also assigned by the mode of inheritance were studied). The results in migrants reveal the following: (1) a higher diversity in the distribution of HLA-A and -DRB1 alleles; (2) lower frequencies of alleles common in our region, such as A0201 B1501, B4001, and DRB10401 and increased frequencies of minor subtypes, such as A3002 and DRB10402; and (3) distinct distributions of B/Cw, DRB1/DQB1 or B/Cw/DRB1/DQB1 haplotypes. The results also revealed that the four most frequent five-allele haplotypes in controls i.e., HLA-A0101/B0801/Cw0701/DRB10301/DQB10201; A0301/B0702/Cw0702/DRB11501/DQB10602 (both of Indo-Celtic origin); A2902/B4403/Cw1601/DRB10701/DQB10202 (frequent in Western-Europeans); and A0201/B1501/Cw0304/DRB10401/DQB10302, represent 10.5% of the total haplotypes in controls but 1.6% in North Africans. Conversely, 9 five-allele haplotypes in multiple copy in North Africans (among which A3002/B1801/Cw0501/DRB10301/DQB10201 of Paleo-North African origin and A0201/B0702/Cw0702/DRB11501/DQB10602 of ancient European and Paleo-North African origin) represent 9.6% of the total haplotypes in North Africans but 2.4% in controls. These results thus suggest a low degree of admixture between the two populations.