بررسی پلی مورفیسم‌های AvaII و BamHI در خوشه ژنی بتا گلوبین و ارتباط آن با بیماری تالاسمی بتا در جمعیت اصفهان

Background: Beta thalassemia is one of the autosomal recessive diseases that related to synthesis disorder of beta globin chain. It is caused by any of the more than 200 mutations in the β-globin gene. DNA sequencing and genotyping of numerous mutations at beta globin gene is timely and expensive. Therefore, the best method for screening is linkage using polymorph markers at beta globin region and it is usually applied at carrier screening and pre-diagnosis. Aim of the present study is frequency determination of AvaII marker at second Intron and BamHI marker at 3´ region of beta globin gene and its association with beta thalassemia disease in Esfahan population. Materials and methods: In the present study, 150 beta-thalassemia patients including 50 individuals without disease as a control group were investigated. After genomic DNA extraction from blood cells, polymorphism genotype of AvaII and BamHI were determined using RFLP-PCR technique. Obtained results were statistically analyzed using Power Marker software package and SISA. Results: G allele frequency of AvaII polymorphism was observed 65.32% at patient groups and 70.59% at control groups this difference was not statistically significant (p=0.29). Genotype distribution of this polymorphism was not statistically significant (p=0.1). T allele frequency of BamHI polymorphism was observed 40.57% at patient groups and 35.63% at control groups, but this difference was not statistically significant (p=0.40). Genotype frequency of this polymorphism was not statistically significant (p=0.6). Linkage disequilibrium results between two markers showed D´ (p=0.064). The best state for two markers ++ and its frequency is 54.33% at control groups and 42.33% at patient groups. Conclusion: No statistically association between AvaII in second Intron and BamHI at 3´ region of beta globin with beta thalassemia disease is expressed that mutant alleles could not to be a risk factor for the disease. However, simultaneous investigation of two markers could be useful.