Please use this identifier to cite or link to this item:
|Title:||Mutation spectrum of RB1 mutations in retinoblastoma cases from Singapore with implications for genetic management and counselling||Authors:||Tomar S.
amino acid substitution
major clinical study
multiplex ligation dependent probe amplification
|Issue Date:||2017||Citation:||Tomar S., Sethi R., Sundar G., Quah T.C., Quah B.L., Lai P.S. (2017). Mutation spectrum of RB1 mutations in retinoblastoma cases from Singapore with implications for genetic management and counselling. PLoS ONE 12 (6) : e0178776. ScholarBank@NUS Repository. https://doi.org/10.1371/journal.pone.0178776||Abstract:||Retinoblastoma (RB) is a rare childhood malignant disorder caused by the biallelic inactivation of RB1 gene. Early diagnosis and identification of carriers of heritable RB1 mutations can improve disease outcome and management. In this study, mutational analysis was conducted on fifty-nine matched tumor and peripheral blood samples from 18 bilateral and 41 unilateral unrelated RB cases by a combinatorial approach of Multiplex Ligation-dependent Probe Amplification (MLPA) assay, deletion screening, direct sequencing, copy number gene dosage analysis and methylation assays. Screening of both blood and tumor samples yielded a mutation detection rate of 94.9% (56/59) while only 42.4% (25/59) of mutations were detected if blood samples alone were analyzed. Biallelic mutations were observed in 43/59 (72.9%) of tumors screened. There were 3 cases (5.1%) in which no mutations could be detected and germline mutations were detected in 19.5% (8/41) of unilateral cases. A total of 61 point mutations were identified, of which 10 were novel. There was a high incidence of previously reported recurrent mutations, occurring at 38.98% (23/59) of all cases. Of interest were three cases of mosaic RB1 mutations detected in the blood from patients with unilateral retinoblastoma. Additionally, two germline mutations previously reported to be associated with low-penetrance phenotypes: missense-c.1981C>T and splice variantc. 607+1G>T, were observed in a bilateral and a unilateral proband, respectively. These findings have implications for genetic counselling and risk prediction for the affected families. This is the first published report on the spectrum of mutations in RB patients from Singapore and shows that further improved mutation screening strategies are required in order to provide a definitive molecular diagnosis for every case of RB. Our findings also underscore the importance of genetic testing in supporting individualized disease management plans for patients and asymptomatic family members carrying low-penetrance, germline mosaicism or heritable unilateral mutational phenotypes. © 2017 Tomar et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.||Source Title:||PLoS ONE||URI:||https://scholarbank.nus.edu.sg/handle/10635/161192||ISSN:||19326203||DOI:||10.1371/journal.pone.0178776|
|Appears in Collections:||Elements|
Show full item record
Files in This Item:
|10_1371_journal_pone_0178776.pdf||2.99 MB||Adobe PDF|
checked on Jul 5, 2020
checked on Jul 2, 2020
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.