rs193922151

Variant names:

• chr17-50189520-CA-C
• rs193922151
• NM_000088.4:c.2685delT

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000088.4(COL1A1):​c.2685delT​(p.Gly896AlafsTer212) 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 (★★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: COL1A1 NM_000088.4 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: -0.0620

Genes affected

COL1A1 (HGNC:2197): (collagen type I alpha 1 chain) This gene encodes the pro-alpha1 chains of type I collagen whose triple helix comprises two alpha1 chains and one alpha2 chain. Type I is a fibril-forming collagen found in most connective tissues and is abundant in bone, cornea, dermis and tendon. Mutations in this gene are associated with osteogenesis imperfecta types I-IV, Ehlers-Danlos syndrome type VIIA, Ehlers-Danlos syndrome Classical type, Caffey Disease and idiopathic osteoporosis. Reciprocal translocations between chromosomes 17 and 22, where this gene and the gene for platelet-derived growth factor beta are located, are associated with a particular type of skin tumor called dermatofibrosarcoma protuberans, resulting from unregulated expression of the growth factor. Two transcripts, resulting from the use of alternate polyadenylation signals, have been identified for this gene. [provided by R. Dalgleish, Feb 2008]

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 17-50189520-CA-C is Pathogenic according to our data. Variant chr17-50189520-CA-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 35916.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr17-50189520-CA-C is described in Lovd as [Likely_pathogenic]. Variant chr17-50189520-CA-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
COL1A1	NM_000088.4	c.2685delT	p.Gly896AlafsTer212	frameshift_variant	Exon 39 of 51	ENST00000225964.10	NP_000079.2
COL1A1	XM_011524341.2	c.2487delT	p.Gly830AlafsTer212	frameshift_variant	Exon 36 of 48		XP_011522643.1
COL1A1	XM_005257059.5	c.1767delT	p.Gly590AlafsTer212	frameshift_variant	Exon 26 of 38		XP_005257116.2
COL1A1	XM_005257058.5	c.2667+158delT		intron_variant	Intron 38 of 48		XP_005257115.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
COL1A1	ENST00000225964.10	c.2685delT	p.Gly896AlafsTer212	frameshift_variant	Exon 39 of 51	1	NM_000088.4	ENSP00000225964.6

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 39

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Osteogenesis imperfecta type I Pathogenic:2

Dec 19, 2024

Genomic Medicine Center of Excellence, King Faisal Specialist Hospital and Research Centre

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Nov 08, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Gly896Alafs*212) in the COL1A1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in COL1A1 are known to be pathogenic (PMID: 7942841, 9295084, 9443882). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with COL1A1-related conditions. ClinVar contains an entry for this variant (Variation ID: 35916). For these reasons, this variant has been classified as Pathogenic. -

Osteogenesis imperfecta Pathogenic:1

Aug 18, 2011

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

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing;curation

- -

not provided Pathogenic:1

Jun 09, 2017

Athena Diagnostics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

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

LitVar

Other links and lift over

dbSNP: rs193922151; hg19: chr17-48266881;