NM_000091.5:c.4981C>A

Variant names:

• chr2-227311838-C-A
• rs201697532
• NM_000091.5:c.4981C>A

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PM1 PM2 PM5 PP3_Strong

The NM_000091.5(COL4A3):​c.4981C>A​(p.Arg1661Ser) variant causes a missense change. The variant allele was found at a frequency of 0.00000137 in 1,461,636 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. R1661C) has been classified as Pathogenic.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: COL4A3 NM_000091.5 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 4.62
• Publications: 0 publications found

Genes affected

COL4A3 (HGNC:2204): (collagen type IV alpha 3 chain) Type IV collagen, the major structural component of basement membranes, is a multimeric protein composed of 3 alpha subunits. These subunits are encoded by 6 different genes, alpha 1 through alpha 6, each of which can form a triple helix structure with 2 other subunits to form type IV collagen. This gene encodes alpha 3. In the Goodpasture syndrome, autoantibodies bind to the collagen molecules in the basement membranes of alveoli and glomeruli. The epitopes that elicit these autoantibodies are localized largely to the non-collagenous C-terminal domain of the protein. A specific kinase phosphorylates amino acids in this same C-terminal region and the expression of this kinase is upregulated during pathogenesis. This gene is also linked to an autosomal recessive form of Alport syndrome. The mutations contributing to this syndrome are also located within the exons that encode this C-terminal region. 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. [provided by RefSeq, Jun 2010]

MFF-DT (HGNC:41067): (MFF divergent transcript)

ACMG classification

Our verdict: Pathogenic. The variant received 10 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, 4 uncertain in NM_000091.5
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr2-227311838-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 287915.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.981

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000091.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	COL4A3	NM_000091.5	MANE Select	c.4981C>A	p.Arg1661Ser	missense	Exon 52 of 52	NP_000082.2	Q01955-1
	MFF-DT	NR_102371.1		n.48-6183G>T		intron	N/A

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	COL4A3	ENST00000396578.8	TSL:1 MANE Select	c.4981C>A	p.Arg1661Ser	missense	Exon 52 of 52	ENSP00000379823.3	Q01955-1
	COL4A3	ENST00000469504.2	TSL:1	n.*306C>A		non_coding_transcript_exon	Exon 6 of 6	ENSP00000493493.1	A0A2R8Y2F0
	COL4A3	ENST00000469504.2	TSL:1	n.*306C>A		3_prime_UTR	Exon 6 of 6	ENSP00000493493.1	A0A2R8Y2F0

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461636 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727104

African (AFR) AF: 0.00 AC: 0 AN: 33472

American (AMR) AF: 0.00 AC: 0 AN: 44720

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26128

East Asian (EAS) AF: 0.00 AC: 0 AN: 39670

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86206

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53408

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5754

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111892

Other (OTH) AF: 0.00 AC: 0 AN: 60386

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.81
BayesDel_addAF	Pathogenic	0.55	D
BayesDel_noAF	Pathogenic	0.55
CADD	Pathogenic	26
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.64	D
Eigen	Uncertain	0.56
Eigen_PC	Uncertain	0.60
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Uncertain	0.95	D
M_CAP	Pathogenic	0.29	D
MetaRNN	Pathogenic	0.98	D
MetaSVM	Uncertain	0.11	D
PhyloP100		4.6
PrimateAI	Uncertain	0.58	T
PROVEAN	Pathogenic	-5.5	D
REVEL	Pathogenic	0.86
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.83
MutPred		0.90		Loss of MoRF binding (P = 0.0099)
MVP		0.95
MPC		0.21
ClinPred		1.0	D
GERP RS		6.1
Varity_R		0.97
gMVP		0.98
Mutation Taster		=22/78	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs201697532; hg19: chr2-228176554;