Haemoglobinopathies in tribal populations of India.

Haemoglobinopathies particularly haemoglobin S and E (HbS, HbE) and β-thalassaemia are important challenges for tribal populations in India. The HbS, HbE and β-thalassaemia genes are variably distributed across various tribal populations of India. HbE is mainly restricted in tribals of North-East, West Bengal, Odisha and those in Andaman and Nicobar islands. HbS has more extensive distribution in the country (10-40% trait frequency) and the homozygotes and double heterozygotes present with a wide array of morbidities. The morbidity varies greatly in different areas of the country due to differential co-inheritance of α-thalassaemia gene and interaction of various epistatic and environmental factors. Though substantial data on prevalence of these disorders exist, there is an urgent need to develop integrated hierarchical core facilities to manage the disease. Such centres will generate more data and will also explore areas of management which need more local attention. Newborn screening, genetic counselling, carrier detection, prenatal diagnosis along with management of cases should form the basic infrastructure of haemoglobinopathy management. Research in this areas should continue focusing on various challenges in care delivery, prevention and basic sciences on interaction of haemoglobinopathies with various other infections.