Congenital ataxic phenotype of <i>ITPR1</i> -related disorder due to novel missense variants – A video case series

The Inositol 1,4,5-triphosphate receptor type 1 (ITPR1) genetic abnormality is known to cause varied phenotypes of ataxia, such as congenital ataxia with global developmental delay, hypotonia and mild cognitive impairment or spinocerebellar ataxia type-29 (SCA29); adult-onset, slowly progressive, predominantly isolated ataxia or spinocerebellar type 15/16 (SCA15/16); or ataxia with iris hypoplasia, also known as Gillespie syndrome (1-5).All three phenotypes are relatively rare, and no reports from India exist.We report three cases from two families diagnosed with congenital ataxia due to novel heterozygous missense variants in the ITPR1 gene.We report three