rs705

chr15-24974365-T-Achr15-24974365-T-Cchr15-24974365-T-G

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_003097.6(SNRPN):c.-89T>A variant causes a 5 prime UTR change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: SNRPN NM_003097.6 5_prime_UTR
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.651

Genes affected

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]

SNHG14 (HGNC:):

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]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.88).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SNRPN	NM_003097.6	c.-89T>A		5_prime_UTR_variant	4/10	ENST00000390687.9
SNHG14	NR_146177.1	n.814T>A		non_coding_transcript_exon_variant	7/148

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SNRPN	ENST00000390687.9	c.-89T>A		5_prime_UTR_variant	4/10	1	NM_003097.6	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Data not reliable, filtered out with message: AC0;AS_VQSR AF: 0.00 AC: 0 AN: 1071934 Hom.: 0 Cov.: 14 AF XY: 0.00 AC XY: 0 AN XY: 552036

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.88
Cadd	Benign	2.2
Dann	Benign	0.77
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.070		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs705; hg19: chr15-25219512;