Novel homozygous HEXB mutation identified in a consanguineous Iranian pedigree with Sandhoff disease

Abstract

Background Sandhoff disease is a rare neurodegenerative and autosomal recessive disorder, characterized by a defect in ganglioside metabolism. It is caused by mutations in the HEXB gene for the β-subunit of β-N-acetyl hexosaminidase. Results In the present study, an Iranian 14- month -old girl with an 8- month history of unsteady walking and involuntary movements is described. Biochemical testing showed defects in the normal activity of beta-hexosaminidase protein. Following sequencing of HEXB gene, a novel homozygous p.A278V mutation was identified in the patient’s DNA. Conclusions The p.A278V mutation is pathogenic because of amino acid change and changing in biochemical activity. this mutation has not been reported previously, but based on In silico analysis and structural analysis, was predicted to be disease causing.