
Genetics of Ataxias in Indian Population: A Collative Insight from a Common Genetic Screening Tool
Author(s) -
Sharma Pooja,
Sonakar Akhilesh Kumar,
Tyagi Nishu,
Suroliya Varun,
Kumar Manish,
Kutum Rintu,
Asokchandran Vivekananda,
Ambawat Sakshi,
Shamim Uzma,
Anand Avni,
Ahmad Ishtaq,
Shakya Sunil,
Uppili Bharathram,
Mathur Aradhana,
Parveen Shaista,
Jain Shweta,
Singh Jyotsna,
Seth Malika,
Zahra Sana,
Joshi Aditi,
Goel Divya,
Sahni Shweta,
Kamai Asangla,
Wadhwa Saruchi,
Murali Aparna,
Saifi Sheeba,
Chowdhury Debashish,
Pandey Sanjay,
Anand Kuljeet Singh,
Narasimhan Ranganathan Lakshmi,
Laskar Sanghamitra,
Kushwaha Suman,
Kumar Mukesh,
Shaji Cheruvallill Velayudhan,
Srivastava Madakasira Vasantha Padma,
Srivastava Achal K.,
Faruq Mohammed
Publication year - 2022
Publication title -
advanced genetics
Language(s) - English
Resource type - Journals
ISSN - 2641-6573
DOI - 10.1002/ggn2.202100078
Subject(s) - cohort , ataxia , etiology , locus (genetics) , allele , genetics , genotype , spinocerebellar ataxia , trinucleotide repeat expansion , population , medicine , disease , biology , pathology , psychiatry , gene , environmental health
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.