RT Journal Article
SR Electronic
T1 Whole-genome analysis as a diagnostic tool for patients referred for diagnosis of Silver-Russell syndrome: a real-world study
JF Journal of Medical Genetics
JO J Med Genet
FD BMJ Publishing Group Ltd
SP jmedgenet-2021-107699
DO 10.1136/jmedgenet-2021-107699
A1 Ahmed S N Alhendi
A1 Derek Lim
A1 Shane McKee
A1 Meriel McEntagart
A1 Katriona Tatton-Brown
A1 I Karen Temple
A1 Justin H Davies
A1 Deborah J G Mackay
YR 2021
UL http://jmg.bmj.com/content/early/2021/06/15/jmedgenet-2021-107699.abstract
AB Background Silver-Russell syndrome (SRS) is an imprinting disorder characterised by prenatal and postnatal growth restriction, but its clinical features are non-specific and its differential diagnosis is broad. Known molecular causes of SRS include imprinting disturbance, single nucleotide variant (SNV), CNV or UPD affecting several genes; however, up to 40% of individuals with a clinical diagnosis of SRS currently receive no positive molecular diagnosis.Methods To determine whether whole-genome sequencing (WGS) could uncover pathogenic variants missed by current molecular testing, we analysed data of 72 participants recruited to the 100,000 Genomes Project within the clinical category of SRS.Results In 20 participants (27% of the cohort) we identified genetic variants plausibly accounting for SRS. Coding SNVs were identified in genes including CDKN1C, IGF2, IGF1R and ORC1. Maternal-effect variants were found in mothers of five participants, including two participants with imprinting disturbance and one with multilocus imprinting disorder. Two regions of homozygosity were suggestive of UPD involving imprinted regions implicated in SRS and Temple syndrome, and three plausibly pathogenic CNVs were found, including a paternal deletion of PLAGL1. In 48 participants with no plausible pathogenic variant, unbiased analysis of SNVs detected a potential association with STX4.Conclusion WGS analysis can detect UPD, CNV and SNV and is potentially a valuable addition to diagnosis of SRS and related growth-restricting disorders.No data are available. WGS data and associated clinical data are held within the 100,000 Genomes Project Research Environment. These data can be accessed by any researcher by application to join a GeCIP domain (www.genomicsengland.co.uk/join-a-gecip-domain/). Informatic scripts are available upon request.