Recurrent and novel GLB1 mutations in India.

Abstract

GM1 gangliosidosis is a lysosomal storage disorder caused by mutations in the GLB1 gene, leading to the deficiency of the enzyme β-d-galactosidase. In this study, we report molecular findings in 50 Asian Indian families with GM1 gangliosidosis. We sequenced all the exons and flanking intronic sequences of GLB1 gene. We identified 33 different mutations (20 novel and 13 previously reported). The novel mutations include 12 missense (p.M1?, p.E129Q, p.G134R, p.L236P, p.G262E, p.L297F, p.Y331C, p.G414V, p.K493N, p.L514P, p.P597L, p.T600I), four splicing (c.246-2A>G, c.397-2A>G, c.552+1G>T, c.956-2A>G), three indels (p.R22Qfs*8, p.L24Cfs*47, p.I489Qfs*4) and one nonsense mutation (p.Q452*). Most common mutations identified in this study were c.75+2InsT (14%) and p.L337P (10%). Known mutations accounted for 67% of allele frequency in our cohort of patients, suggesting that these mutations in GLB1 are recurrent across different populations. Twenty three mutations were localized in the TIM barrel domain, β-domain 1 and β-domain 2. In silico sequence and structure analysis of GLB1 reveal that all the novel mutations affect the function and structure of the protein. We hereby report on the largest series of patients with GM1 gangliosidosis and the first from India.

• Authors: Abdul Mueed Bidchol, Ashwin Dalal, Rakesh Trivedi, Anju Shukla, Sheela Nampoothiri, V H Sankar, Sumita Danda, Neerja Gupta, Madhulika Kabra, Shrikiran A Hebbar, Ramesh Y Bhat, Divya Matta, Alka V Ekbote, Ratna Dua Puri, Shubha R Phadke, Kalpana Gowrishankar, Shagun Aggarwal, Prajnya Ranganath, Sheetal Sharda, Mahesh Kamate, Chaitanya A Datar, Kamalakshi Bhat, Nutan Kamath, Hitesh Shah, Shuba Krishna, Puthiya Mundyat Gopinath, Ishwar C Verma, H A Nagarajaram, Kapaettu Satyamoorthy, Katta Mohan Girisha
• Journal: Gene (Gene) Vol. 567 Issue 2 Pg. 173-81 (Aug 10 2015) ISSN: 1879-0038 [Electronic] Netherlands
• PMID: 25936995 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2015 Elsevier B.V. All rights reserved.

Chemical References

• GLB1 protein, human
• beta-Galactosidase

Topics

• Child, Preschool
• DNA Mutational Analysis
• Female
• Gangliosidosis, GM1 (genetics)
• Genetic Association Studies
• Heterozygote
• Humans
• India
• Infant
• Infant, Newborn
• Male
• Models, Molecular
• Mutation, Missense
• Polymorphism, Single Nucleotide
• beta-Galactosidase (genetics)