Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2PP3_Moderate
The NM_003384.3(VRK1):c.397C>G(p.Arg133Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).
VRK1 (HGNC:12718): (VRK serine/threonine kinase 1) This gene encodes a member of the vaccinia-related kinase (VRK) family of serine/threonine protein kinases. This gene is widely expressed in human tissues and has increased expression in actively dividing cells, such as those in testis, thymus, fetal liver, and carcinomas. Its protein localizes to the nucleus and has been shown to promote the stability and nuclear accumulation of a transcriptionally active p53 molecule and, in vitro, to phosphorylate Thr18 of p53 and reduce p53 ubiquitination. This gene, therefore, may regulate cell proliferation. This protein also phosphorylates histone, casein, and the transcription factors ATF2 (activating transcription factor 2) and c-JUN. [provided by RefSeq, Jul 2008]
Broad Center for Mendelian Genomics, Broad Institute of MIT and Harvard
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: research
The homozygous p.Arg133Gly variant in VRK1 was identified by our study in one individual with Pontocerebellar Hypoplasia. This variant was absent from large population studies. Computational prediction tools and conservation analyses do not provide strong support for or against an impact to the protein. However, a likely pathogenic variant curated by our study at the the same position, (p.Arg133Cys), has been reported in individuals with Pontocerebellar Hypoplasia and segregated with disease in 4 affected relatives from 1 cosanguineous family (PMID: 21937992). In summary, the clinical significance of this variant is uncertain. -