Molecular characterization of β-thalassemia in four communities in South Gujarat—codon 30 (G → A) a predominant mutation in the Kachhiya Patel community

Abstract

Different thalassemia mutations have been reported in various ethnic groups and geographical regions in India. In this study, we have investigated Kachhiya Patel, Dhodia Patel, Modh Bania, and Muslim communities of Surat, Gujarat to identify molecular defects causing β-thalassemia in them. Covalent reverse dot blot hybridization technique was used to detect six common Indian β-thalassemia mutations while the seventh mutation (619-bp deletion) was identified by PCR. The less common mutations were detected by amplification refractory mutation and the uncharacterized samples were directly sequenced. Characterization of β-thalassemia mutations was carried out in a total of 175 unrelated β-thalassemia trait cases. We identified IVS 1 nt 5 (G → C) in 31 out of 65 Muslims, codon (Cd) 41/42 (-CTTT) in 14 out of 16 in Modh Banias, Cd 15 (G → A) in 19 out of 24 Dhodia Patels. The most significant observation was an uncommon mutation; Cd 30 (G → A) detected in 61 out of 70 Kachhiya Patels. The 619-bp deletion was detected in 6 out of 10 Muslim-Memons. Many other rare mutations like Cd 15 (-T), Cd 8 (-AA), -88 (C → A), Capsite +1 (A → C), Cd 16(-C), and Cd 5 (-CT) were detected. To our knowledge, our study is the first to characterize β-thalassemia mutations in the Kachhiya Patel community. This study will facilitate molecular analysis and prenatal diagnosis in these four communities.