Mistri, M.A. and Dalal, Ashwin and Nath, P. and Nampoothiri, S. and Mehta, S. and Singh, A. and Sheth, F. and Sheth, J. (2018) Identification of novel and known mutation in 19 patients with mucolipidosis type II and III from India and validation of novel method of screening for mucolipidosis-II and III screening. Molecular Genetics and Metabolism, 123 (2). s96. ISSN 1096-7192

Text Mol Genet Metab 123 s96.pdf Restricted to Repository staff only Download (57Kb) | Request a copy

Abstract

Mucolipidosis-II and III (ML-II and III) are an autosomal recessive lysosomal disorders caused due to impaired activity of lysosomal enzyme N-acetylglucosamine-1-phosphotransferase; composed of three subunits (α,β, γ) encoded by two genes-GNPTAB and GNPTG. Mutation in GNPTAB results in ML-II and ML-III(α/β) whereas mutation in GNPTG results in ML-III(γ). As per HGMD database, 134 mutations in GNPTAB and 24 mutations in GNPTG gene have been reported from the different ethnic group, although disease-causing mutations are not known in Indian subjects. Hence, the present study was undertaken as a part of a national task force multicentric project to identify a molecular spectrum of GNPTAB and GNPTG genes in Indian patients. Additionally, this study has enabled to validate indigenously developed screening test for ML-II/III, to evaluate genotype-phenotype correlations and to establish common disease-causing mutations that can be utilized as a common molecular screening test in Indian patients. Present study consists of 19 children presented in the age range of 0.5 to 8 years. They have first screened for ML-II/III screening method followed by confirmative enzymes study from plasma. This was followed by mutation study using Sanger sequencing. The study has identified 16 mutations in 19 patients. Ten of them are novel, 9 in GNPTAB gene [p.T382P, p.R986H, p.W1201X, c.3336-1G > A, c.2675_2676dupT, c.2693_2694dupA, c.2954_2955dupCACAAAGT, c.73266_73473dup and c.1021_1023delCCA] and 1 in GNPTG gene [p.W108X]. Five previously reported mutations [p.R334Q, p.E968D, c.3335 + 1G > A, c.3503_3504delTC and g.65610_65610delA] in GNPTAB gene and one [p.C157X] in GNPTG gene were also identified. The most common mutation was frame-shift mutation c.3503_3504delTC, accounted for 41% of the patients. To conclude, c.3503_3504delTC seems to the common mutation in Indian patients. Our study also demonstrates that all patients who are screened positive were confirmed to have ML-II/III by enzymes and molecular study this validates our screening test for ML-II/III with 100% sensitivity and specificity.

Item Type:	Article
Depositing User:	Users 2 not found.
Date Deposited:	22 Jul 2015 06:57
Last Modified:	02 Aug 2020 19:42
URI:	http://cdfd.sciencecentral.in/id/eprint/277

Actions (login required)

View Item