In view of the paucity of deletion studies of survival of motor neuron (SMN) and neuronal apoptosis inhibitor protein (NAIP) genes in Indian SMA patients, this study has been undertaken to determine the status of SMN1, SMN2 and NAIP gene deletions in Indian SMA patients. Clinically and neurophysiologically diagnosed SMA patients were included in the study. A gene deletion study was carried out in 45 proximal SMA patients and 50 controls of the same ethnic group. Both SMN1 and NAIP genes showed homozygous absence in 76 % and 31 % respectively in proximal SMA patients. It is proposed that the lower deletion frequency of SMN1 gene in Indian patients may be due to mutations present in other genes or population variation, which need further study
