rs121912852

Positions:

• chr3-48570304-G-A

Variant summary

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

The NM_000094.4(COL7A1):​c.7411C>T​(p.Arg2471Ter) variant causes a stop gained change. The variant allele was found at a frequency of 0.00000205 in 1,461,858 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: COL7A1 NM_000094.4 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 3.94

Genes affected

COL7A1 (HGNC:2214): (collagen type VII alpha 1 chain) This gene encodes the alpha chain of type VII collagen. The type VII collagen fibril, composed of three identical alpha collagen chains, is restricted to the basement zone beneath stratified squamous epithelia. It functions as an anchoring fibril between the external epithelia and the underlying stroma. Mutations in this gene are associated with all forms of dystrophic epidermolysis bullosa. In the absence of mutations, however, an acquired form of this disease can result from an autoimmune response made to type VII collagen. [provided by RefSeq, Jul 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 3-48570304-G-A is Pathogenic according to our data. Variant chr3-48570304-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 17459.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
COL7A1	NM_000094.4	c.7411C>T	p.Arg2471Ter	stop_gained	98/119	ENST00000681320.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
COL7A1	ENST00000681320.1	c.7411C>T	p.Arg2471Ter	stop_gained	98/119		NM_000094.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000796 AC: 2 AN: 251368 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135870

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000327

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461858 Hom.: 0 Cov.: 34 AF XY: 0.00000138 AC XY: 1 AN XY: 727242

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: 0.0000232

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000824 AC: 1

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Nov 15, 2019	Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss-of-function is a known mechanism of disease; Not observed at a significant frequency in large population cohorts (Lek et al., 2016); This variant is associated with the following publications: (PMID: 31001817, 25525159, 16271705, 18558993, 21448560, 8644729, 29473190) -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 01, 2024	This sequence change creates a premature translational stop signal (p.Arg2471*) in the COL7A1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in COL7A1 are known to be pathogenic (PMID: 16971478). This variant is present in population databases (rs121912852, gnomAD 0.003%). This premature translational stop signal has been observed in individual(s) with clinical features of autosomal recessive epidermolysis bullosa dystrophica (PMID: 8644729, 29473190, 31001817). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 17459). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

Epidermolysis bullosa dystrophica Pathogenic:1

Pathogenic, no assertion criteria provided

clinical testing

Natera, Inc.

Jul 20, 2020

- -

Recessive dystrophic epidermolysis bullosa Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Apr 01, 1996

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.56	D
BayesDel_noAF	Pathogenic	0.51
CADD	Pathogenic	41
DANN	Uncertain	1.0
Eigen	Uncertain	0.67
Eigen_PC	Uncertain	0.48
FATHMM_MKL	Uncertain	0.89	D
MutationTaster	Benign	1.0	A;A
Vest4		0.82
GERP RS		4.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.040		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: rs121912852; hg19: chr3-48607737; COSMIC: COSV60394853; COSMIC: COSV60394853;