A Rare Case of Ataxia-Telangiectasia-Like Disorder With MRE11 Mutation

The prototypical disorder for the early-onset cerebellar ataxia with cerebellar atrophy is ataxia telangiectasia (AT). AT belongs to "DNA-repair defects" or "DNA-repair deficiency" disorders. The ATM (Ataxia-telangiectasia mutated kinase) gene mutated in AT is central to deoxyribonucleic acid (DNA) damage response (DDR) signaling. Other genes implicated in DDR signaling are MRE11A (Meiotic recombination 11). Mutation of this gene results in ataxia-telangiectasia-like disorder (ATLD). We report a boy who presented with mild cerebellar ataxia and dystonia with cerebellar atrophy on brain imaging. Clinical exome sequencing showed compound heterozygous variants in MRE11 gene. He was diagnosed as ATLD, which has not been reported in Indian subcontinent so far.