3-48584486-G-T

Variant names:

• chr3-48584486-G-T
• rs140403507
• NM_000094.4:c.4118C>A

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_000094.4(COL7A1):​c.4118C>A​(p.Ser1373*) variant causes a stop gained, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,788 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: COL7A1 NM_000094.4 stop_gained, splice_region
• Scores: Splicing: ADA: 0.6006
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 1.72

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 10 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

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
COL7A1	NM_000094.4	c.4118C>A	p.Ser1373*	stop_gained, splice_region_variant	Exon 36 of 119	ENST00000681320.1	NP_000085.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
COL7A1	ENST00000681320.1	c.4118C>A	p.Ser1373*	stop_gained, splice_region_variant	Exon 36 of 119		NM_000094.4	ENSP00000506558.1
COL7A1	ENST00000328333.12	c.4118C>A	p.Ser1373*	stop_gained, splice_region_variant	Exon 35 of 118	1		ENSP00000332371.8
COL7A1	ENST00000487017.5	n.35C>A		splice_region_variant, non_coding_transcript_exon_variant	Exon 1 of 83	5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251332 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135820

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: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461788 Hom.: 0 Cov.: 34 AF XY: 0.00000275 AC XY: 2 AN XY: 727196

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: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000824 AC: 1

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.29
CADD	Pathogenic	37
DANN	Uncertain	1.0
Eigen	Uncertain	0.37
Eigen_PC	Benign	0.12
FATHMM_MKL	Benign	0.22	N
Vest4		0.75
GERP RS		3.6

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.60
dbscSNV1_RF	Benign	0.60
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: rs140403507; hg19: chr3-48621919;