Publications by authors named "Srilekha Sundaramurthy"
Background: Congenital stationary night blindness (CSNB) is a group of genetically and clinically heterogeneous non-progressive retinal disorders and can be classified based on fundus abnormalities as found in Oguchi disease or fundus albipunctatus (FA) or based on the absence of severe fundus abnormalities but altered electroretinography (ERG) findings. Here, we report the clinical and genetic findings of 46 CSNB families, with 18 families showing fundus abnormalities and 28 families without fundus abnormalities but having an altered ERG, showing complete CSNB (cCSNB) and Riggs type CSNB.
Methodology: Ophthalmic examinations including full-field ERG recordings, colour vision test, optical coherence tomography and fundus autofluorescence were performed and candidate genes for CSNB were screened by panel-based next-generation sequencing using an Illumina MiSeq platform.
Article Synopsis
- Congenital stationary night blindness (CSNB) is a genetic eye condition often linked to high myopia, which can lead to serious retinal issues, making understanding myopic progression crucial for potential treatments.
- The study analyzed cases of CSNB associated with specific genetic variants in patients under 18 who had multiple eye measurements, using a mixed-effect model to track changes in myopia over time.
- Results showed that individuals with CSNB are significantly myopic from birth and continue to experience worsening myopia as they grow, suggesting they may benefit from treatments aimed at slowing down myopia progression.
Article Synopsis
- Inherited retinal dystrophies (IRD), particularly retinitis pigmentosa (RP), lead to progressive loss of vision, affecting photoreceptors, with genetic testing identifying causative mutations in 70-80% of RP cases.
- This study analyzed 107 RP patients using next-generation sequencing to correlate genetic mutations with specific retinal features, finding 72 patients with pathogenic mutations and documenting symptom onset around age 14.
- Results revealed distinct phenotype characteristics associated with certain gene mutations, suggesting that genetic testing not only aids in diagnosis but also enhances patient counseling for future treatments and prognosis.
Article Synopsis
- The study focuses on genetic testing for primary mutations associated with Leber hereditary optic neuropathy (LHON) in India, analyzing 278 suspected patients from 2014-2018.
- Among the patients tested, 29.4% (82/278) were found to carry one of the three common mitochondrial DNA mutations, with the m.11778G>A mutation being the most prevalent.
- The average age of visual loss onset for those with a primary mutation was around 21 years, with typical symptoms including painless vision loss and specific visual field defects.
Leber hereditary optic neuropathy-new insights and old challenges.
Graefes Arch Clin Exp Ophthalmol
September 2021
Leber hereditary optic neuropathy (LHON) is the most common primary mitochondrial DNA (mtDNA) disorder with the majority of patients harboring one of three primary mtDNA point mutations, namely, m.3460G>A (MTND1), m.11778G>A (MTND4), and m.
View Article and Find Full Text PDFInherited retinal degeneration (IRD) are a group of genetically heterogeneous disease of which retinitis pigmentosa (RP) and Leber congenital amaurosis (LCA) are the most common and severe type. In our study we had taken three unrelated South Indian consanguineous IRD families. Homozygosity mapping was done using Affymetrix 250K Nsp1 GeneChip in each of LCA, Cone-Rod dystrophy (CRD) and autosomal recessive RP (arRP) families followed by targeted re-sequencing by next generation sequencing (NGS) on Illumina MiSeq.
View Article and Find Full Text PDFLeber congenital amaurosis (LCA) and retinitis pigmentosa (RP) are retinal degenerative diseases which cause severe retinal dystrophy affecting the photoreceptors. LCA is predominantly inherited as an autosomal recessive trait and contributes to 5% of all retinal dystrophies; whereas RP is inherited by all the Mendelian pattern of inheritance and both are leading causes of visual impairment in children and young adults. Homozygosity mapping is an efficient strategy for mapping both known and novel disease loci in recessive conditions, especially in a consanguineous mating, exploiting the fact that the regions adjacent to the disease locus will also be homozygous by descent in such inbred children.
View Article and Find Full Text PDFPurpose: To screen for possible disease-causing mutations in rhodopsin (RHO), pre-mRNA processing factor 31 (PRPF31), retinitis pigmentosa 1 (RP1), and inosine monophosphate dehydrogenase 1 (IMPDH1) genes in Indian patients with isolated and autosomal dominant forms of retinitis pigmentosa (adRP). Information on such data is not available in India and hence this study was undertaken.
Methods: Blood samples were obtained from 48 isolated and 53 adRP patients, who were recruited for the study.
Purpose: To determine the frequency of pathogenic mutations in the gene encoding RPE65 in patients from India with Leber congenital amaurosis (LCA).
Methods: The coding sequence of all 14 exons and the adjacent flanking intron sequences of the RPE65 gene were directly sequenced in 60 unrelated Indian LCA patients. Bioinformatics tool was used to study the structural changes of the mutant protein.