rs121912857

Positions:

• chr13-110187181-C-G
• chr13-110187181-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM2 PM5 PP2 PP3_Strong

The ENST00000375820.10(COL4A1):​c.1685G>C​(p.Gly562Ala) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,688 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G562E) has been classified as Pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: COL4A1 ENST00000375820.10 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.14

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr13-110187181-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 17414.Status of the report is no_assertion_criteria_provided, 0 stars.
• 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, 0.977

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COL4A1	NM_001845.6	c.1685G>C	p.Gly562Ala	missense_variant	25/52	ENST00000375820.10	NP_001836.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
COL4A1	ENST00000375820.10	c.1685G>C	p.Gly562Ala	missense_variant	25/52	1	NM_001845.6	ENSP00000364979	P1
COL4A1	ENST00000649738.1	n.1815G>C		non_coding_transcript_exon_variant	25/31

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251348 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135850

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

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: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461688 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727148

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.69
BayesDel_addAF	Pathogenic	0.52	D
BayesDel_noAF	Pathogenic	0.60
CADD	Uncertain	23
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.91	D
Eigen	Pathogenic	0.86
Eigen_PC	Pathogenic	0.76
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.95	D
M_CAP	Pathogenic	0.91	D
MetaRNN	Pathogenic	0.98	D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	3.8	H
MutationTaster	Benign	1.0	D;D
PrimateAI	Pathogenic	0.81	D
PROVEAN	Pathogenic	-5.7	D
REVEL	Pathogenic	0.94
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.94
MutPred		0.76		Gain of catalytic residue at A558 (P = 0.001);
MVP		0.99
MPC		0.54
ClinPred		0.99	D
GERP RS		4.7
Varity_R		0.69
gMVP		0.99

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: rs121912857; hg19: chr13-110839528;