4. Carrier screening of alpha thalassemia using sequencing method
Main Article Content
Abstract
Αlpha thalassemia is mainly caused by deletion mutations in the HBA1 and HBA2 genes, but about 5% of the disease is caused by point mutations. Mutations in the HBA1 and HBA2 genes cause a deficiency in the α-globin chain that makes up the hemoglobin molecule. Depending on the number of missing α chains, the clinical manifestations of the disease are at different levels. The disease is inherited autosomal recessive, so the identification of healthy people carrying the disease is important in genetic counseling to reduce the rate of children with the disease in the community. The study was conducted with the following objectives: Identify non-deletional mutations of HBA1 and HBA2 genes by Sanger sequencing technique. Subjects and methods: Blood samples of 9 cases suspected of carrying the α-thalassemia gene but no gene deletion mutations were selected for the study; DNA was extracted from peripheral blood; Gene sequencing technique was applied to identify point mutations of HBA1 and HBA2 genes. Results: 4 types of non-deletional mutations of the HBA2 gene have been identified in 9 heterozygous carriers, of which 5/9 carrier having mutations -αHbCs, 2/9 carrier having mutations --αHbQs, 1/9 carrier having mutations c.2delT and carrier having a novel mutation c.-2C>T have not been reported in the databases.
Article Details
Keywords
α- thalassemia carriers, Sanger sequencing, non- deletional mutation
References
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