Rare β- and δ-Globin Gene Mutations in the Pathare Prabhus: Original Inhabitants of Mumbai, India.

Genetic structure of the Indian population is influenced by waves of several immigrants from West Eurasia. Therefore, genetic information of various ethnic groups is valuable to understand their origins, the pattern of migration as well as the genetic relationship between them. No genetic data is available on Pathare Prabhu, which is a small indigenous Hindu community from Mumbai, Maharashtra State, India. The aim of this study was to screen the Pathare Prabhus for hemoglobinopathies, which is a major public health problem in India. Two hundred and fifty-seven unrelated Pathare Prabhus subjects were screened for various hemoglobinopathies. Complete blood counts (CBC) were done on an automated hematology counter. High performance liquid chromatography (HPLC) was used to identify β-thalassemia (β-thal) carriers. Molecular characterization of the β gene defects was done by reverse dot-blot hybridization, amplification refractory mutation system (ARMS) and DNA sequencing. Deletional α-thalassemia (α-thal) was detected by multiplex polymerase chain reaction (PCR). Hb A2 -Saurashtra (HBD: c.301C>T) was identified by DNA sequencing; its modeling was also done. The prevalence of β-thal was 3.89%, while deletional α-thal was 5.4%. The initiation codon (ATG>ACG) (HBB: c.2T>C) was seen in eight individuals (80.0%), Hb D-Punjab (HBB: c.364G>C) and Hb A2 -Saurashtra, was found in two and one individual, respectively. A community-specific β-thal mutation was found in Pathare Prabhus in significant proportions. This information is useful in developing an algorithm for a prenatal diagnosis (PND) program.