title: Sequence-Based analysis of the HLA-DRB1 polymorphism in Metalsa Berber and Chaouya Arabic-speaking groups from Morocco.
abstract: To examine the genetic diversity in Morocco, the polymorphism at the HLA-DRB1 locus was investigated in two populations: the Metalsa group consisting of Berbers from north Morocco (who speak the Tarifit language and live in the Nador area), and the Chaouya group who are Arabic-speaking people from west Morocco (Atlantic coast) living in the Settat area. The DRB1 alleles of 197 healthy unrelated individuals were identified by direct DNA sequencing of exon 2 using fluorescently-labeled primers. A total of 28 and 29 alleles at DRB1 locus were identified in the Metalsa and Chaouya groups, respectively. The most frequent alleles in the Metalsa group are DRB1*03011 (20.2%), DRB1*0701 (12.12%), and DRB1*1302 (11.11%). In the Chaouya group, DRB1*0701 (16.33%), DRB1*15011 (12.76%), and DRB1*03011 (11.73%) are most common. Each population exhibits some specific variants and some uncommon alleles. The frequency of the DRB1*03011 allele differs significantly between the two populations (p = 0.0311). The DRB1 frequency distributions in the two groups suggest the effects of balancing selection. The interpopulation analysis highlighted a strong relatedness, based on genetic distances, between the two Moroccan groups and the other north Africans (the Moroccans from El Jadida area, Moroccan Souss Berbers, Algerians, and Tunisians), and to a lesser extent with the Iberians, French, and Ethiopians.
authors.affiliation: Laboratoire d'Immunologie, Institut National D'Hygiene, Rabat, Morocco.
authors.forename: Khadija
authors.initials: K
authors.lastname: Oumhani
authors.forename: Angelica
authors.initials: A
authors.lastname: Canossi
authors.forename: Daniela
authors.initials: D
authors.lastname: Piancatelli
authors.forename: Marilena
authors.initials: M
authors.lastname: Di Rocco
authors.forename: Tiziana
authors.initials: T
authors.lastname: Del Beato
authors.forename: Gabriella
authors.initials: G
authors.lastname: Liberatore
authors.forename: Anna
authors.initials: A
authors.lastname: Aureli
authors.forename: Abdelaziz
authors.initials: A
authors.lastname: Benjoaud
authors.forename: Rajae
authors.initials: R
authors.lastname: El Aouad
authors.forename: Domenico
authors.initials: D
authors.lastname: Adorno
authors.forename: Carlo Umberto
authors.initials: CU
authors.lastname: Casciani
authors.forename: Abd Elaziz
authors.initials: AE
authors.lastname: Ben Jouad
mesh_terms: D005787:Gene Frequency; D005819:Genetic Markers; D006684:HLA-DR Antigens / Q000032:analysis* / Q000235:genetics*; D059811:HLA-DRB1 Chains; D006801:Humans; D009018:Morocco / Q000208:ethnology; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D017422:Sequence Analysis, DNA
chemical_list: D005819:Genetic Markers; D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains