chr2-227010423-T-C

Position:

• chr2-227010423-T-C

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1 PM2 PP3_Strong

The NM_000092.5(COL4A4):​c.4412A>G​(p.His1471Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: not found (cov: 33)
• Consequence: COL4A4 NM_000092.5 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.99

Genes affected

COL4A4 (HGNC:2206): (collagen type IV alpha 4 chain) This gene encodes one of the six subunits of type IV collagen, the major structural component of basement membranes. This particular collagen IV subunit, however, is only found in a subset of basement membranes. Like the other members of the type IV collagen gene family, this gene is organized in a head-to-head conformation with another type IV collagen gene so that each gene pair shares a common promoter. Mutations in this gene are associated with type II autosomal recessive Alport syndrome (hereditary glomerulonephropathy) and with familial benign hematuria (thin basement membrane disease). Two transcripts, differing only in their transcription start sites, have been identified for this gene and, as is common for collagen genes, multiple polyadenylation sites are found in the 3' UTR. [provided by RefSeq, Jul 2008]

COL4A4 (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM1: In a domain Collagen IV NC1 (size 225) in uniprot entity CO4A4_HUMAN there are 16 pathogenic changes around while only 3 benign (84%) in NM_000092.5
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.959

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COL4A4	NM_000092.5	c.4412A>G	p.His1471Arg	missense_variant	46/48	ENST00000396625.5	NP_000083.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
COL4A4	ENST00000396625.5	c.4412A>G	p.His1471Arg	missense_variant	46/48	5	NM_000092.5	ENSP00000379866.3
COL4A4	ENST00000682098.1	c.79A>G	p.Thr27Ala	missense_variant	1/3			ENSP00000508331.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000756

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.95
BayesDel_addAF	Pathogenic	0.45	D
BayesDel_noAF	Pathogenic	0.41
CADD	Uncertain	24
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.63	D
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.93
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.96	D
M_CAP	Pathogenic	0.34	D
MetaRNN	Pathogenic	0.96	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.9	H
PrimateAI	Uncertain	0.70	T
PROVEAN	Pathogenic	-7.1	D
REVEL	Pathogenic	0.92
Sift	Uncertain	0.0040	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.92
MutPred		0.82		Gain of disorder (P = 0.0769);
MVP		0.95
MPC		0.17
ClinPred		0.99	D
GERP RS		5.7
Varity_R		0.86
gMVP		0.86

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: rs762796207; hg19: chr2-227875139;