title: HLA class II genetic diversity in southern Tunisia and the Mediterranean area.
abstract: North Africa is populated by many Arab- and Berber-speaking populations whose genetic history is still poorly understood. In this study, we analyse the HLA-DRB1 and DQB1 molecular diversity in three populations from the south of Tunisia--Berbers from Jerba, Berbers from Matmata and Arabs from Gabes--and we compare them to a large set of populations from the whole Mediterranean region. Among the three populations studied, the Berbers from Jerba are the most peculiar, as they diverge significantly from other North Africans while being genetically highly diversified and close to populations from the Near East. Thus, Jerba may have been a crossing point, in historical times, where colonization from the eastern Mediterranean area left significant genetic traces. By contrast, the populations from Matmata and Gabes are genetically similar to other Arab and Berber-speaking populations from different areas of the Maghrib, despite some peculiar allele and haplotype frequencies. At a larger scale, northwest Africa and southwest Europe are closely related according to these polymorphisms, while the populations from the eastern Mediterranean area are much more differentiated. The close genetic relatedness found for HLA among populations of the western Mediterranean region challenges previous results based on Y chromosome analyses, where the Gibraltar Strait appeared to constitute a main genetic barrier.
authors.affiliation: Regional Center of Blood Transfusion, Gabes, Tunisia.
authors.forename: B
authors.initials: B
authors.lastname: Abdennaji Guenounou
authors.forename: B Yacoubi
authors.initials: BY
authors.lastname: Loueslati
authors.forename: S
authors.initials: S
authors.lastname: Buhler
authors.forename: S
authors.initials: S
authors.lastname: Hmida
authors.forename: H
authors.initials: H
authors.lastname: Ennafaa
authors.forename: H
authors.initials: H
authors.lastname: Khodjet-Elkhil
authors.forename: N
authors.initials: N
authors.lastname: Moojat
authors.forename: A
authors.initials: A
authors.lastname: Dridi
authors.forename: K
authors.initials: K
authors.lastname: Boukef
authors.forename: A
authors.initials: A
authors.lastname: Ben Ammar Elgaaied
authors.forename: A
authors.initials: A
authors.lastname: Sanchez-Mazas
mesh_terms: D000483:Alleles; D005787:Gene Frequency; D014644:Genetic Variation; D005828:Genetics, Population; D006683:HLA-DQ Antigens / Q000235:genetics*; D059866:HLA-DQ beta-Chains; D006684:HLA-DR Antigens / Q000235:genetics*; D059811:HLA-DRB1 Chains; D006239:Haplotypes; D006801:Humans; D019083:Mediterranean Region; D014416:Tunisia
chemical_list: D006683:HLA-DQ Antigens; D059866:HLA-DQ beta-Chains; C069051:HLA-DQB1 antigen; D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains