title: Identification of β-globin haplotypes linked to sickle hemoglobin (Hb S) alleles in Mazandaran province, Iran.
abstract: Carrier frequency of the βSallele has been reported to be 0.19% in Mazandaran province, northern Iran. Haplotype analysis of the βSallele helps trace the origin of its encoded hemoglobin (Hb) variant, Hb S, in a region. The aim of this study was to investigate the haplotypes associated with βSalleles in Mazandaran province. Capillary electrophoresis was carried out to detect individuals suspected to have a βSallele(s). DNA analysis (PCR-RFLP) was used for final confirmation. To identify 5' to 3' β-globin gene cluster haplotypes associated with βSalleles, family linkage analysis was applied. Six polymorphic sites (HincII 5' to ε, XmnI 5' toGγ, HindIII inGγ, HindIII inAγ, HincII 3' to ψβ and AvaII in β) were investigated using the PCR-RFLP method. Five different haplotypes were linked to βSalleles, while βAalleles were associated with nine haplotypes. Among the βSalleles, 53.9% were associated with the Benin (----++) haplotype, and the Arab-Indian (+++-++) haplotype had the second-highest frequency (23%). Unlike southern provinces, where the Arab-Indian haplotype is prominent, the Benin haplotype is the most frequent haplotype in northern Iran, and this may represent a founder effect. Since the Benin haplotype does not carry the XmnI polymorphism 5' to theGγ gene, which is responsible for high expression of Hb F, a severe form of sickle cell disease can be anticipated in patients that are homozygous for the βSallele in the northern region.
authors.affiliation: Thalassemia Research Center, Mazandaran University of Medical Sciences.
authors.forename: Faeghe
authors.initials: F
authors.lastname: Aghajani
authors.affiliation: Thalassemia Research Center, Mazandaran University of Medical Sciences.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Mahdavi
authors.affiliation: Thalassemia Research Center, Mazandaran University of Medical Sciences.
authors.forename: Mehrnoush
authors.initials: M
authors.lastname: Kosaryan
authors.affiliation: Sina Mehr Research Center.
authors.forename: Mehrad
authors.initials: M
authors.lastname: Mahdavi
authors.affiliation: Thalassemia Research Center, Mazandaran University of Medical Sciences.
authors.forename: Mohaddase
authors.initials: M
authors.lastname: Hamidi
authors.affiliation: Thalassemia Research Center, Mazandaran University of Medical Sciences.
authors.forename: Hossein
authors.initials: H
authors.lastname: Jalali
mesh_terms: D000483:Alleles; D000755:Anemia, Sickle Cell / Q000235:genetics*; D006239:Haplotypes; D006451:Hemoglobin, Sickle / Q000235:genetics*; D006801:Humans; D007492:Iran; D012150:Polymorphism, Restriction Fragment Length; D055544:beta-Globins / Q000235:genetics*
chemical_list: D006451:Hemoglobin, Sickle; D055544:beta-Globins
keywords: PCR-RFLP; haplotype; βS allele