Profiling β-thalassaemia mutations in India at state and regional levels: implications for genetic education, screening and counselling programmes

Abstract

Thalassaemia and sickle cell disease have been recognized by the World Health Organization as important inherited disorders principally impacting on the populations of low income countries. To create a national and regional profile of b-thalassaemia mutations in the population of India, a meta-analysis was conducted on 17 selected studies comprising 8,505 alleles and offering nearnational coverage for the disease. At the national level 52 mutations accounted for 97.5% of all b-thalassaemia alleles, with IVSI-5(G[C) the most common disease allele (54.7%). Population stratification was apparent in the mutation profiles at regional level with, for example, the prevalence of IVSI-5(G[C) varying from 44.8% in the North to 71.4% in the East. A number of major mutations, such as Poly A(T[C), were apparently restricted to a particular region of the country, although these findings may in part reflect the variant test protocols adopted by different centres. Given the size and genetic complexity of the Indian population, and with specific mutations for b-thalassaemia known to be strongly associated with individual communities, comprehensive disease registries need to be compiled at state, district and community levels to ensure the efficacy of genetic education, screening and counselling programmes. At the same, time appropriately designed community-based studies are required as a health priority to correct earlier sampling inequities which resulted in the under-representation of many communities, in particular rural and socioeconomically under-privileged groups.

Molecular Basis of β-Thalassemia in Karnataka, India

“…The spectrum of mutations that are reported in this study confirm the heterogeneity observed in the different population groups within India (Bhasin et al , 1994; Edison et al , 2008; Colah et al , 2009; Sinha et al , 2009b). Population screening associated with genetic counseling is particularly helpful by allowing families at risk to make informed decision on their reproductive choices.…”

Molecular Basis of β-Thalassemia in Karnataka, India

“…The spectrum of mutations that are reported in this study confirm the heterogeneity observed in the different population groups within India (Bhasin et al , 1994; Edison et al , 2008; Colah et al , 2009; Sinha et al , 2009b). Population screening associated with genetic counseling is particularly helpful by allowing families at risk to make informed decision on their reproductive choices.…”

Cross-Sectional Study for the Detection of Mutations in the Beta-Globin Gene Among Patients with Hemoglobinopathies in the Bengali Population

“…This mutation is mostly found in zone 2 (6.48%). As per previous report, the frequency is 1.6% in northern Indian population, whereas in Central and South Indians, frequencies are 3.5% and 8.8%, respectively (Sinha et al, 2009).…”

Haemoglobinopathies in eastern Indian states: a demographic evaluation

“…A better understanding of the diversity can be obtained through studies on larger sample size with expanded areas of collection. So far, 52 different BTT mutations have been recorded in India (Sinha et al 2009), of which only 18 have been reported in Uttar Pradesh (Agrawal et al 2000). In the present study, however, we found only eight BTT mutations in all the regions put together.…”

Molecular Basis of β-Thalassemia in Karnataka, India

“…The spectrum of mutations that are reported in this study confirm the heterogeneity observed in the different population groups within India (Bhasin et al , 1994; Edison et al , 2008; Colah et al , 2009; Sinha et al , 2009b). Population screening associated with genetic counseling is particularly helpful by allowing families at risk to make informed decision on their reproductive choices.…”

Cross-Sectional Study for the Detection of Mutations in the Beta-Globin Gene Among Patients with Hemoglobinopathies in the Bengali Population

“…This mutation is mostly found in zone 2 (6.48%). As per previous report, the frequency is 1.6% in northern Indian population, whereas in Central and South Indians, frequencies are 3.5% and 8.8%, respectively (Sinha et al, 2009).…”

Haemoglobinopathies in eastern Indian states: a demographic evaluation

“…A better understanding of the diversity can be obtained through studies on larger sample size with expanded areas of collection. So far, 52 different BTT mutations have been recorded in India (Sinha et al 2009), of which only 18 have been reported in Uttar Pradesh (Agrawal et al 2000). In the present study, however, we found only eight BTT mutations in all the regions put together.…”

Molecular Basis of β-Thalassemia in Karnataka, India

“…The spectrum of mutations that are reported in this study confirm the heterogeneity observed in the different population groups within India (Bhasin et al , 1994; Edison et al , 2008; Colah et al , 2009; Sinha et al , 2009b). Population screening associated with genetic counseling is particularly helpful by allowing families at risk to make informed decision on their reproductive choices.…”

Cross-Sectional Study for the Detection of Mutations in the Beta-Globin Gene Among Patients with Hemoglobinopathies in the Bengali Population

“…This mutation is mostly found in zone 2 (6.48%). As per previous report, the frequency is 1.6% in northern Indian population, whereas in Central and South Indians, frequencies are 3.5% and 8.8%, respectively (Sinha et al, 2009).…”

Haemoglobinopathies in eastern Indian states: a demographic evaluation

“…A better understanding of the diversity can be obtained through studies on larger sample size with expanded areas of collection. So far, 52 different BTT mutations have been recorded in India (Sinha et al 2009), of which only 18 have been reported in Uttar Pradesh (Agrawal et al 2000). In the present study, however, we found only eight BTT mutations in all the regions put together.…”