3-48578930-G-A

Variant names:

• chr3-48578930-G-A
• NM_000094.4:c.5413C>T

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1 PM2 PP2

The NM_000094.4(COL7A1):​c.5413C>T​(p.Pro1805Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,662 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P1805L) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: COL7A1 NM_000094.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 2.96

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]

MIR711 (HGNC:37316): (microRNA 711) microRNAs (miRNAs) are short (20-24 nt) non-coding RNAs that are involved in post-transcriptional regulation of gene expression in multicellular organisms by affecting both the stability and translation of mRNAs. miRNAs are transcribed by RNA polymerase II as part of capped and polyadenylated primary transcripts (pri-miRNAs) that can be either protein-coding or non-coding. The primary transcript is cleaved by the Drosha ribonuclease III enzyme to produce an approximately 70-nt stem-loop precursor miRNA (pre-miRNA), which is further cleaved by the cytoplasmic Dicer ribonuclease to generate the mature miRNA and antisense miRNA star (miRNA*) products. The mature miRNA is incorporated into a RNA-induced silencing complex (RISC), which recognizes target mRNAs through imperfect base pairing with the miRNA and most commonly results in translational inhibition or destabilization of the target mRNA. The RefSeq represents the predicted microRNA stem-loop. [provided by RefSeq, Sep 2009]

ACMG classification

Verdict is Uncertain_significance. Variant got 5 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 2 uncertain in NM_000094.4
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the COL7A1 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 223 curated pathogenic missense variants (we use a threshold of 10). The gene has 262 curated benign missense variants. Gene score misZ: 1.5899 (below the threshold of 3.09). Trascript score misZ: 4.0428 (above the threshold of 3.09). GenCC associations: The gene is linked to recessive dystrophic epidermolysis bullosa, dystrophic epidermolysis bullosa pruriginosa, recessive dystrophic epidermolysis bullosa-generalized other, transient bullous dermolysis of the newborn, epidermolysis bullosa with congenital localized absence of skin and deformity of nails, generalized dominant dystrophic epidermolysis bullosa, dystrophic epidermolysis bullosa, nails only, acral dystrophic epidermolysis bullosa, recessive dystrophic epidermolysis bullosa inversa, pretibial dystrophic epidermolysis bullosa.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
COL7A1	NM_000094.4	c.5413C>T	p.Pro1805Ser	missense_variant	Exon 63 of 119	ENST00000681320.1	NP_000085.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
COL7A1	ENST00000681320.1	c.5413C>T	p.Pro1805Ser	missense_variant	Exon 63 of 119		NM_000094.4	ENSP00000506558.1
COL7A1	ENST00000328333.12	c.5413C>T	p.Pro1805Ser	missense_variant	Exon 62 of 118	1		ENSP00000332371.8
MIR711	ENST00000390201.1	n.48C>T		non_coding_transcript_exon_variant	Exon 1 of 1	6
COL7A1	ENST00000487017.5	n.1330C>T		non_coding_transcript_exon_variant	Exon 28 of 83	5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461662 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 727124

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Uncertain:1

May 04, 2022

Mendelics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided Uncertain:1

Jun 29, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces proline, which is neutral and non-polar, with serine, which is neutral and polar, at codon 1805 of the COL7A1 protein (p.Pro1805Ser). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with COL7A1-related conditions. ClinVar contains an entry for this variant (Variation ID: 1686592). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on COL7A1 protein function. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.12
BayesDel_addAF	Pathogenic	0.18	D
BayesDel_noAF	Uncertain	0.020
CADD	Uncertain	26
DANN	Uncertain	1.0
DEOGEN2	Benign	0.37	T
Eigen	Uncertain	0.55
Eigen_PC	Uncertain	0.52
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.90	D
M_CAP	Uncertain	0.24	D
MetaRNN	Uncertain	0.56	D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Uncertain	2.3	M
PrimateAI	Benign	0.47	T
PROVEAN	Benign	-1.8	N
REVEL	Uncertain	0.50
Sift	Benign	0.030	D
Sift4G	Uncertain	0.025	D
Polyphen		1.0	D
Vest4		0.28
MutPred		0.46		Loss of glycosylation at K1801 (P = 0.0239);
MVP		0.94
MPC		0.25
ClinPred		0.63	D
GERP RS		5.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.097
gMVP		0.92

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.060		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: chr3-48616363;