1-42746730-TGA-T

Position:

• chr1-42746730-TGA-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PVS1_Moderate PM2 PP5_Moderate

The NM_022356.4(P3H1):​c.2176_2177del​(p.Ser726ArgfsTer3) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Likely pathogenic (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: P3H1 NM_022356.4 frameshift
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 2.07

Genes affected

P3H1 (HGNC:19316): (prolyl 3-hydroxylase 1) This gene encodes an enzyme that is a member of the collagen prolyl hydroxylase family. These enzymes are localized to the endoplasmic reticulum and their activity is required for proper collagen synthesis and assembly. Mutations in this gene are associated with osteogenesis imperfecta type VIII. Three alternatively spliced transcript variants encoding different isoforms have been described. Other variants may exist, but their biological validity has not been determined. [provided by RefSeq, Aug 2011]

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 0.0158 CDS is truncated, and there are 1 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 1-42746730-TGA-T is Pathogenic according to our data. Variant chr1-42746730-TGA-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 2827796.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
P3H1	NM_022356.4	c.2176_2177del	p.Ser726ArgfsTer3	frameshift_variant	15/15	ENST00000296388.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
P3H1	ENST00000296388.10	c.2176_2177del	p.Ser726ArgfsTer3	frameshift_variant	15/15	1	NM_022356.4	P1

Frequencies

GnomAD3 genomes Cov.: 33

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 33

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Osteogenesis imperfecta type 8 Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 26, 2023

This sequence change creates a premature translational stop signal (p.Ser726Argfs*3) in the P3H1 gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 11 amino acid(s) of the P3H1 protein. This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with P3H1-related conditions. This variant disrupts the KDEL domain (p.Lys733-p.Leu736) of the P3H1 protein that is required for the cellular retention and activity of certain types of proteins (PMID: 3545499). In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Computational scores

Source: dbNSFP v4.3

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr1-43212401;