title: β-Globin gene cluster haplotypes of Hb D-Los Angeles in Mazandaran Province, Iran.
abstract: Several types of hemoglobin D (Hb D) are distinguishable by DNA analysis, and the aim of this study was to identify the types of Hb D variant and β-globin gene haplotypes linked to Hb D in Mazandaran Province, northern Iran. Fifty five individuals were identified as Hb D carriers, and PCR-RFLP analysis revealed that all 55 had the Hb D-Los Angeles type. To identify haplotypes associated with the β(D) allele, family linkage analysis, using the PCR-RFLP method for seven polymorphisms in the β-globin gene cluster, was carried out on families of 23 of these 55 individuals. We observed three different haplotypes in association with Hb D-Los Angeles. In most cases (91.4%) β(D) alleles were linked to haplotype I [+ - - - - + +]. Haplotype II [- + + - + + +] and an atypical haplotype [- + + - - + -] were each in association with the β(D) allele in only one case (4.3%). This is the first report worldwide of the [- + + - - + -] haplotype in association with Hb D-Los Angeles. We conclude that more than 90% of the evaluated Hb D-Los Angeles alleles in Mazandaran have the same origin, and the two rare haplotypes may represent different genetic origins and/or other molecular events, such as gene conversion or recombination, in the region.
authors.affiliation: Thalassemia Research Center, Hemoglobinopathy Institute, Mazandaran University of Medical Sciences.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Mahdavi
authors.forename: Hossein
authors.initials: H
authors.lastname: Jalali
authors.forename: Mehrnoush
authors.initials: M
authors.lastname: Kosaryan
authors.forename: Payam
authors.initials: P
authors.lastname: Roshan
authors.forename: Mehrad
authors.initials: M
authors.lastname: Mahdavi
mesh_terms: D000483:Alleles; D004252:DNA Mutational Analysis; D004909:Erythrocyte Indices; D008040:Genetic Linkage; D006239:Haplotypes; D006455:Hemoglobins, Abnormal / Q000235:genetics*; D006801:Humans; D007492:Iran; D005810:Multigene Family; D009154:Mutation; D055544:beta-Globins / Q000235:genetics*
chemical_list: D006455:Hemoglobins, Abnormal; D055544:beta-Globins; C026237:hemoglobin D Punjab