rs12902137

chr15-24679516-T-Achr15-24679516-T-C

Variant summary

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

The NM_018958.3(NPAP1):c.*178T>A variant causes a 3 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: 33)
• Consequence: NPAP1 NM_018958.3 3_prime_UTR
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.0720

Genes affected

NPAP1 (HGNC:1190): (nuclear pore associated protein 1) This intronless retrogene is located in the Prader-Willi syndrome region on chromosome 15. This gene exhibits tissue-specific imprinting. Expression in adult testis and brain is biallelic, while expression in fetal brain is monoallelic and only from the paternal chromosome. The encoded protein is associated with the nuclear pore complex. [provided by RefSeq, Mar 2021]

PWRN1 (HGNC:33235): (Prader-Willi region non-protein coding RNA 1) This gene is located in the Prader-Willi syndrome (PWS) region of chromosome 15, which is known to undergo imprinting. The transcript is believed to be non-coding. It is bi-allelically expressed in testis and kidney, but mono-allelically expressed from the paternal allele in brain. This gene is poly-adenylated and is known to undergo alternative splicing. Transcript variants may represent part of a complex imprinting center-SNURF-SNRPN transcription unit. The contribution of this gene to the PWS phenotype is unknown, but it has been suggested that it may play a role in establishing paternal imprinting in the PWS region, perhaps by maintaining the paternal allele in an open chromatin configuration. [provided by RefSeq, Sep 2009]

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=-0.95).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
NPAP1	NM_018958.3	c.*178T>A		3_prime_UTR_variant	1/1	ENST00000329468.5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
NPAP1	ENST00000329468.5	c.*178T>A		3_prime_UTR_variant	1/1		NM_018958.3	P1
PWRN1	ENST00000652025.1	n.1487+55411T>A		intron_variant, non_coding_transcript_variant
PWRN1	ENST00000652139.1	n.605-52763T>A		intron_variant, non_coding_transcript_variant
PWRN1	ENST00000652735.1	n.892+55411T>A		intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 4

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.95
Cadd	Benign	2.8
Dann	Benign	0.60

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		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: rs12902137; hg19: chr15-24924663;