chr3-48570639-C-A

Variant names:

• chr3-48570639-C-A
• rs201728948
• NM_000094.4:c.7344G>T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_000094.4(COL7A1):​c.7344G>T​(p.Val2448Val) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000138 in 1,452,268 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. V2448V) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: COL7A1 NM_000094.4 synonymous
• Scores: Splicing: ADA: 0.9377
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.0210
• Publications: 0 publications found

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]

COL7A1 Gene-Disease associations (from GenCC):

• epidermolysis bullosa with congenital localized absence of skin and deformity of nails

  Inheritance: AD, AR Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), G2P
• dystrophic epidermolysis bullosa pruriginosa

  Inheritance: AR, AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet, G2P
• recessive dystrophic epidermolysis bullosa

  Inheritance: AR, AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, G2P, Ambry Genetics, ClinGen, Orphanet, PanelApp Australia
• generalized dominant dystrophic epidermolysis bullosa

  Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet, Labcorp Genetics (formerly Invitae), PanelApp Australia
• transient bullous dermolysis of the newborn

  Inheritance: AD, AR Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Genomics England PanelApp
• pretibial dystrophic epidermolysis bullosa

  Inheritance: AR, AD Classification: STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet
• acral dystrophic epidermolysis bullosa

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• dystrophic epidermolysis bullosa, nails only

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• recessive dystrophic epidermolysis bullosa inversa

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• recessive dystrophic epidermolysis bullosa-generalized other

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.62).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000094.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	COL7A1	NM_000094.4	MANE Select	c.7344G>T	p.Val2448Val	synonymous	Exon 96 of 119	NP_000085.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	COL7A1	ENST00000681320.1	MANE Select	c.7344G>T	p.Val2448Val	synonymous	Exon 96 of 119	ENSP00000506558.1
	COL7A1	ENST00000328333.12	TSL:1	c.7344G>T	p.Val2448Val	synonymous	Exon 95 of 118	ENSP00000332371.8
	COL7A1	ENST00000422991.1	TSL:5	c.339G>T	p.Val113Val	splice_region synonymous	Exon 5 of 10	ENSP00000391608.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000138 AC: 2 AN: 1452268 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 721516

African (AFR) AF: 0.00 AC: 0 AN: 33194

American (AMR) AF: 0.00 AC: 0 AN: 43484

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25872

East Asian (EAS) AF: 0.0000255 AC: 1 AN: 39200

South Asian (SAS) AF: 0.00 AC: 0 AN: 85106

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52716

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5756

European-Non Finnish (NFE) AF: 9.03e-7 AC: 1 AN: 1107012

Other (OTH) AF: 0.00 AC: 0 AN: 59928

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.62
CADD	Benign	21
DANN	Benign	0.89
PhyloP100		0.021

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.94
dbscSNV1_RF	Benign	0.69
SpliceAI score (max)		0.46		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.46		Position offset: 7

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

Other links and lift over

dbSNP: rs201728948; hg19: chr3-48608072;