Sickle cell disease in India: the journey and hope for the future.

India, the most populous nation in the world, also has a high frequency of the sickle hemoglobin (HbS) allele globally. The Arab Indian HbS haplotype in India is characterized by a relatively high percentage of fetal Hb, with widely varying frequencies of α-thalassemia. Hence, sickle cell disease (SCD) in India was perceived to be mild. Advances in the past decade in screening and SCD management have revealed that the severity of SCD in India is comparable to many other parts of the world. Clinical features in India include vaso-occlusive crisis, acute chest syndrome, avascular necrosis, renal involvement, stroke, etc, at a relatively young age. Once a fatal disease of childhood, the majority of patients born with SCD are expected to survive into adulthood, largely because of improvements in comprehensive care programs including newborn screening, penicillin prophylaxis, transcranial Doppler, and hydroxyurea therapy. Several centers are performing hematopoietic stem cell transplants successfully for SCD. To address the urgent need to control and manage SCD in India's population, the Government of India launched the National Sickle Cell Anaemia Elimination Mission, with significant funding for large-scale measures to screen, treat, counsel, educate, and develop technologies and novel therapies and gene therapies.