2-227089922-C-G

Position:

• chr2-227089922-C-G

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PS1 PM2 PP3_Strong

The NM_000092.5(COL4A4):​c.1405G>C​(p.Gly469Arg) 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. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another nucleotide change resulting in same amino acid change has been previously reported as Likely pathogenicin Lovd.

• Frequency: Genomes: not found (cov: 31)
• Consequence: COL4A4 NM_000092.5 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 4.18

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]

ACMG classification

Verdict is Pathogenic. Variant got 10 ACMG points.

• PS1: Transcript NM_000092.5 (COL4A4) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in Lovd
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.99

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COL4A4	NM_000092.5	c.1405G>C	p.Gly469Arg	missense_variant	21/48	ENST00000396625.5	NP_000083.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
COL4A4	ENST00000396625.5	c.1405G>C	p.Gly469Arg	missense_variant	21/48	5	NM_000092.5	ENSP00000379866	P1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 31

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.86
BayesDel_addAF	Pathogenic	0.51	D
BayesDel_noAF	Pathogenic	0.49
CADD	Pathogenic	27
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.54	D
Eigen	Pathogenic	0.76
Eigen_PC	Uncertain	0.64
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Uncertain	0.89	D
M_CAP	Pathogenic	0.47	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Uncertain	2.7	M
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.72	T
PROVEAN	Pathogenic	-6.8	D
REVEL	Pathogenic	0.91
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.0020	D
Polyphen		1.0	D
Vest4		0.95
MutPred		0.90		Gain of MoRF binding (P = 0.0074);
MVP		0.86
MPC		0.67
ClinPred		0.98	D
GERP RS		6.0
Varity_R		0.55
gMVP		0.88

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: rs926605269; hg19: chr2-227954638;