chr3-52075981-ACTGT-A

Position:

• chr3-52075981-ACTGT-A

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PVS1_Moderate PM2 PP3_Moderate

The NM_015426.5(POC1A):​c.1126_1129del​(p.Thr376SerfsTer8) variant causes a frameshift, splice region change. The variant allele was found at a frequency of 0.000000685 in 1,460,390 control chromosomes in the GnomAD database, with no homozygous occurrence. 1/1 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: POC1A NM_015426.5 frameshift, splice_region
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.82

Genes affected

POC1A (HGNC:24488): (POC1 centriolar protein A) POC1 proteins contain an N-terminal WD40 domain and a C-terminal coiled coil domain and are part of centrosomes. They play an important role in basal body and cilia formation. This gene encodes one of the two POC1 proteins found in humans. Mutations in this gene result in short stature, onychodysplasia, facial dysmorphism, and hypotrichosis (SOFT) syndrome. [provided by RefSeq, Sep 2012]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.0801 CDS is truncated, and there are 0 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
POC1A	NM_015426.5	c.1126_1129del	p.Thr376SerfsTer8	frameshift_variant, splice_region_variant	11/11	ENST00000296484.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
POC1A	ENST00000296484.7	c.1126_1129del	p.Thr376SerfsTer8	frameshift_variant, splice_region_variant	11/11	1	NM_015426.5	P1
POC1A	ENST00000394970.6	c.982_985del	p.Thr328SerfsTer8	frameshift_variant, splice_region_variant	10/10	1
POC1A	ENST00000474012.1	c.1012_1015del	p.Thr338SerfsTer8	frameshift_variant, splice_region_variant	11/11	2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460390 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 726624

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: 0.0000166

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Jun 27, 2023

Variant summary: POC1A c.1126_1129delACAG (p.Thr376SerfsX8) results in a premature termination codon, predicted to cause a truncation of the encoded protein. Nonsense mediated decay is not expected in this region. No variants downstream of this position have been classified as pathogenic by our laboratory or other ClinVar submitters. The variant was absent in 251412 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.1126_1129delACAG in individuals affected with Short stature-onychodysplasia-facial dysmorphism-hypotrichosis syndrome and no experimental evidence demonstrating its impact on protein function have been reported. No submitters have cited clinical-significance assessments for this variant to ClinVar after 2014. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.34		Position offset: 0
DS_AL_spliceai		1.0		Position offset: 4

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr3-52109997;