Oculomasticatory rhythmic movements, insomnia and stroke-like episodes in a patient with POLG mutation.

The POLG mutation, a leading cause of mitochondrial diseases, exhibits a wide-ranging age of onset and a complex clinical presentation. We encountered an atypical clinical profile in an elderly man with a POLG mutation, characterised by a stroke-like episode, chronic insomnia and transient oculomasticatory rhythmic movement. History revealed chronic constipation since his 50s and progressive bilateral ophthalmoplegia since his early 60s. Subsequently, he had experienced acute encephalopathy and later developed chronic insomnia. The present neurological examination showed bilateral complete ophthalmoplegia, ptosis, and rhythmic ocular and jaw movements. Imaging indicated findings suggestive of a stroke-like episode and eventual genetic analysis revealed a homozygous missense mutation in the POLG gene. This case expands the clinical spectrum of POLG mutations in individuals over 60 years, showcasing the rare combination of a stroke-like episode, chronic insomnia and oculomasticatory rhythmic movement.

Genetics of Ataxias in Indian Population: A Collative Insight from a Common Genetic Screening Tool.

Cerebellar ataxias (CAs) represent a group of autosomal dominant and recessive neurodegenerative disorders affecting cerebellum with or without spinal cord. Overall, CAs have preponderance for tandem nucleotide repeat expansions as an etiological factor (10 TREs explain nearly 30-40% of ataxia cohort globally). The experience of 10 years of common genetic ataxia subtypes for ≈5600 patients' referrals (Pan-India) received at a single center is shared herein. Frequencies (in %, n) of SCA types and FRDA in the sample cohort are observed as follows: SCA12 (8.6%, 490); SCA2 (8.5%, 482); SCA1 (4.8%, 272); SCA3 (2%, 113); SCA7 (0.5%, 28); SCA6 (0.1%, 05); SCA17 (0.1%, 05), and FRDA (2.2%, 127). A significant amount of variability in TRE lengths at each locus is observed, we noted presence of biallelic expansion, co-occurrence of SCA-subtypes, and the presence of premutable normal alleles. The frequency of mutated GAA-FRDA allele in healthy controls is 1/158 (0.63%), thus an expected FRDA prevalence of 1:100 000 persons. The data of this study are relevant not only for clinical decision making but also for guidance in direction of genetic investigations, transancestral comparison of genotypes, and lastly provide insight for policy decision for the consideration of SCAs under rare disease category.