Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2BP4_Moderate
The NM_001394334.1(SNURF):c.130C>T(p.Arg44Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000147 in 1,613,860 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 11/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).
SNURF (HGNC:11171): (SNRPN upstream open reading frame) This gene is located within the Prader-Willi Syndrome critical region on chromosome 15. Transcripts produced from this gene initiate at an imprinting center and are paternally-imprinted. These transcripts may be bicistronic and also encode SNRPN (small nuclear ribonucleoprotein polypeptide N) from a downstream open reading frame. The small protein represented by this gene is encoded by an evolutionarily-conserved upstream open reading frame and is localized to the nucleus. Extensive alternative splicing and promoter usage occurs in this region and the full-length nature of some of these transcripts has not been determined. Alterations in the imprinting center are associated with parental imprint switch failure, which may cause Angelman syndrome or Prader-Willi syndrome. [provided by RefSeq, Mar 2017]
SNRPN (HGNC:11164): (small nuclear ribonucleoprotein polypeptide N) This gene is located within the Prader-Willi Syndrome critical region on chromosome 15 and is imprinted and expressed from the paternal allele. It encodes a component of the small nuclear ribonucleoprotein complex, which functions in pre-mRNA processing and may contribute to tissue-specific alternative splicing. Alternative promoter use and alternative splicing result in a multitude of transcript variants encoding the same protein. Transcript variants that initiate at the CpG island-associated imprinting center may be bicistronic and also encode the SNRPN upstream reading frame protein (SNURF) from an upstream open reading frame. In addition, long spliced transcripts for small nucleolar RNA host gene 14 (SNHG14) may originate from the promoters at this locus and share exons with this gene. Alterations in this region are associated with parental imprint switch failure, which may cause Angelman syndrome or Prader-Willi syndrome. [provided by RefSeq, Mar 2017]
Uncertain significance, criteria provided, single submitter
clinical testing
Ambry Genetics
Jan 03, 2022
The c.130C>T (p.R44C) alteration is located in exon 3 (coding exon 3) of the SNURF gene. This alteration results from a C to T substitution at nucleotide position 130, causing the arginine (R) at amino acid position 44 to be replaced by a cysteine (C). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -