rs672601349

Positions:

• chr13-110181363-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM2 PP2 PP3_Strong PP5

The NM_001845.6(COL4A1):​c.2122G>A​(p.Gly708Arg) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (no stars). Synonymous variant affecting the same amino acid position (i.e. G708G) has been classified as Benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: COL4A1 NM_001845.6 missense
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 6.17

Genes affected

COL4A1 (HGNC:2202): (collagen type IV alpha 1 chain) This gene encodes a type IV collagen alpha protein. Type IV collagen proteins are integral components of basement membranes. This gene shares a bidirectional promoter with a paralogous gene on the opposite strand. The protein consists of an amino-terminal 7S domain, a triple-helix forming collagenous domain, and a carboxy-terminal non-collagenous domain. It functions as part of a heterotrimer and interacts with other extracellular matrix components such as perlecans, proteoglycans, and laminins. In addition, proteolytic cleavage of the non-collagenous carboxy-terminal domain results in a biologically active fragment known as arresten, which has anti-angiogenic and tumor suppressor properties. Mutations in this gene cause porencephaly, cerebrovascular disease, and renal and muscular defects. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Dec 2014]

COL4A1 (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), COL4A1. . Gene score misZ 3.0194 (greater than the threshold 3.09). Trascript score misZ 4.972 (greater than threshold 3.09). GenCC has associacion of gene with brain small vessel disease 1 with or without ocular anomalies, pontine autosomal dominant microangiopathy with leukoencephalopathy, muscular dystrophy-dystroglycanopathy, type A, microangiopathy and leukoencephalopathy, pontine, autosomal dominant, familial porencephaly, autosomal dominant familial hematuria-retinal arteriolar tortuosity-contractures syndrome, retinal arterial tortuosity.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.991
• PP5: Variant 13-110181363-C-T is Pathogenic according to our data. Variant chr13-110181363-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 161977.Status of the report is no_assertion_criteria_provided, 0 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COL4A1	NM_001845.6	c.2122G>A	p.Gly708Arg	missense_variant	29/52	ENST00000375820.10	NP_001836.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
COL4A1	ENST00000375820.10	c.2122G>A	p.Gly708Arg	missense_variant	29/52	1	NM_001845.6	ENSP00000364979.4
COL4A1	ENST00000649738.1	n.2252G>A		non_coding_transcript_exon_variant	29/31

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 35

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: no assertion criteria provided

Submissions by phenotype

Brain small vessel disease 1 with or without ocular anomalies Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Jan 01, 2009

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.54	D
BayesDel_noAF	Pathogenic	0.54
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.91	D
Eigen	Pathogenic	0.72
Eigen_PC	Uncertain	0.47
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.94	D
M_CAP	Pathogenic	0.83	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	4.3	H
PrimateAI	Uncertain	0.79	T
PROVEAN	Pathogenic	-6.7	D
REVEL	Pathogenic	0.91
Sift	Benign	0.035	D
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		0.98
MutPred		0.74		Gain of catalytic residue at P709 (P = 0.0028);
MVP		0.96
MPC		0.58
ClinPred		1.0	D
GERP RS		4.9
Varity_R		0.76
gMVP		1.0

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: rs672601349; hg19: chr13-110833710;