Prevalence of b-thalassaemia in subcastes of Indian Sindhis: Results from a two-phase survey
To estimate the prevalence of b-thalassaemia in different subcastes of the Indian Sindhi population who, in general, have a high prevalence of this disease. Study design: A two-phase, community-based survey. Methods: Asymptomatic, Sindhi volunteers from Nagpur, central India, were recruited into the present study over a 7-year period. The first phase included the use of the Naked Eye Single Tube Red cell Osmotic Fragility Test (NESTROFT). Those positive for NESTROFT or those volunteering for haemoglobin A2 (HbA2) quantification entered the second phase of the survey. Appropriate statistical methods for estimating prevalence from two-phase surveys were used. Results: The prevalence of b-thalassaemia carriers across the five major Sindhi subcastes varied substantially in the study population. Larkana Sindhis had the highest (17%) whereas Dadu Sindhis had the lowest (8%) frequency of the b-thalassaemia allele. As a corollary, the projected incidence of b-thalassaemia major in newborn babies greatly varied by the subcastes of the parents. Conclusion: Ethnic subgroups within populations known to commonly carry the b-thalassaemia gene provide further information that is useful from epidemiological and public health perspectives.
Public Health. 2007; 121:193-8.
By: Jawahirani A, Mamtani M, Das K, Rughwani V, Kulkarni H