NM_001846.4:c.-203T>G

Variant names:

• chr13-110307370-T-G
• rs7991332
• NM_001846.4:c.-203T>G

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_001846.4(COL4A2):​c.-203T>G variant causes a 5 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000066 in 151,574 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: COL4A2 NM_001846.4 5_prime_UTR
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.182
• Publications: 4 publications found

Genes affected

COL4A2 (HGNC:2203): (collagen type IV alpha 2 chain) This gene encodes one of the six subunits of type IV collagen, the major structural component of basement membranes. The C-terminal portion of the protein, known as canstatin, is an inhibitor of angiogenesis and tumor growth. 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, Jul 2008]

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 Gene-Disease associations (from GenCC):

• brain small vessel disease 1 with or without ocular anomalies

  Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet, G2P, Genomics England PanelApp
• autosomal dominant familial hematuria-retinal arteriolar tortuosity-contractures syndrome

  Inheritance: AD Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Ambry Genetics, Genomics England PanelApp, Orphanet
• microangiopathy and leukoencephalopathy, pontine, autosomal dominant

  Inheritance: AD Classification: MODERATE Submitted by: Ambry Genetics
• familial porencephaly

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• pontine autosomal dominant microangiopathy with leukoencephalopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• retinal arterial tortuosity

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• muscular dystrophy-dystroglycanopathy, type A

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.8).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001846.4. 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
	COL4A2	NM_001846.4	MANE Select	c.-203T>G		5_prime_UTR	Exon 1 of 48	NP_001837.2	P08572
	COL4A1	NM_001845.6	MANE Select	c.-343A>C		upstream_gene	N/A	NP_001836.3	P02462-1
	COL4A1	NM_001303110.2		c.-343A>C		upstream_gene	N/A	NP_001290039.1	P02462-2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	COL4A2	ENST00000360467.7	TSL:5 MANE Select	c.-203T>G		5_prime_UTR	Exon 1 of 48	ENSP00000353654.5	P08572
	COL4A2	ENST00000714399.1		c.-203T>G		5_prime_UTR	Exon 1 of 49	ENSP00000519666.1	A0AAQ5BHW7
	COL4A2	ENST00000907571.1		c.-203T>G		5_prime_UTR	Exon 1 of 48	ENSP00000577630.1

Frequencies

GnomAD3 genomes AF: 0.00000660 AC: 1 AN: 151574 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 91110 Hom.: 0 Cov.: 0 AF XY: 0.00 AC XY: 0 AN XY: 45646

African (AFR) AF: 0.00 AC: 0 AN: 2970

American (AMR) AF: 0.00 AC: 0 AN: 2346

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3434

East Asian (EAS) AF: 0.00 AC: 0 AN: 7250

South Asian (SAS) AF: 0.00 AC: 0 AN: 1202

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 7078

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 540

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 59928

Other (OTH) AF: 0.00 AC: 0 AN: 6362

GnomAD4 genome AF: 0.00000660 AC: 1 AN: 151574 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 73996

African (AFR) AF: 0.00 AC: 0 AN: 41294

American (AMR) AF: 0.00 AC: 0 AN: 15262

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3466

East Asian (EAS) AF: 0.00 AC: 0 AN: 5076

South Asian (SAS) AF: 0.00 AC: 0 AN: 4824

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10540

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 314

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 67804

Other (OTH) AF: 0.00 AC: 0 AN: 2084

Alfa AF: 0.00 Hom.: 654

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.80
CADD	Benign	13
DANN	Benign	0.54
PhyloP100		-0.18
PromoterAI		0.016	Neutral

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

Other links and lift over

dbSNP: rs7991332; hg19: chr13-110959717;