rs188122235

Positions:

• chr13-110167148-G-A

Variant summary

Our verdict is Benign. Variant got -20 ACMG points: 0P and 20B. BP4_Strong BP6_Very_Strong BS1 BS2

The NM_001845.6(COL4A1):​c.3949+10C>T variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000797 in 1,611,318 control chromosomes in the GnomAD database, including 11 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.0045 (5 hom., cov: 32)
  • Exomes 𝑓: 0.00041 (6 hom.)
• Consequence: COL4A1 NM_001845.6 intron
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:8
• Conservation: PhyloP100: -2.88

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 Benign. Variant got -20 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.9).
• BP6: Variant 13-110167148-G-A is Benign according to our data. Variant chr13-110167148-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 311033.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr13-110167148-G-A is described in Lovd as [Benign].
• BS1: Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.0045 (685/152282) while in subpopulation AFR AF= 0.0156 (649/41550). AF 95% confidence interval is 0.0146. There are 5 homozygotes in gnomad4. There are 323 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck.
• BS2: High AC in GnomAd4 at 685 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COL4A1	NM_001845.6	c.3949+10C>T		intron_variant		ENST00000375820.10	NP_001836.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
COL4A1	ENST00000375820.10	c.3949+10C>T		intron_variant		1	NM_001845.6	ENSP00000364979	P1
COL4A1	ENST00000650424.1	c.105+10C>T		intron_variant				ENSP00000497477

Frequencies

GnomAD3 genomes AF: 0.00449 AC: 683 AN: 152164 Hom.: 5 Cov.: 32

Gnomad AFR AF: 0.0156

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00183

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: 0.00335

GnomAD3 exomes AF: 0.00117 AC: 293 AN: 251460 Hom.: 3 AF XY: 0.000890 AC XY: 121 AN XY: 135904

Gnomad AFR exome AF: 0.0165

Gnomad AMR exome AF: 0.000520

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000327

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000879

Gnomad OTH exome AF: 0.000814

GnomAD4 exome AF: 0.000411 AC: 600 AN: 1459036 Hom.: 6 Cov.: 33 AF XY: 0.000346 AC XY: 251 AN XY: 725996

Gnomad4 AFR exome AF: 0.0150

Gnomad4 AMR exome AF: 0.000827

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000232

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000171

Gnomad4 OTH exome AF: 0.000630

GnomAD4 genome AF: 0.00450 AC: 685 AN: 152282 Hom.: 5 Cov.: 32 AF XY: 0.00434 AC XY: 323 AN XY: 74448

Gnomad4 AFR AF: 0.0156

Gnomad4 AMR AF: 0.00183

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00331

Alfa AF: 0.00355 Hom.: 0

Bravo AF: 0.00558

Asia WGS AF: 0.00115 AC: 4 AN: 3478

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:8

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Benign:4

Benign, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 21, 2024	- -
Likely benign, criteria provided, single submitter	clinical testing	Center for Pediatric Genomic Medicine, Children's Mercy Hospital and Clinics	Jun 12, 2017	- -
Likely benign, criteria provided, single submitter	not provided	Breakthrough Genomics, Breakthrough Genomics	-	- -
Likely benign, criteria provided, single submitter	clinical testing	GeneDx	Sep 18, 2018	- -

Brain small vessel disease 1 with or without ocular anomalies Benign:2

Benign, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 13, 2018	This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -
Likely benign, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jun 14, 2016	- -

Autosomal dominant familial hematuria-retinal arteriolar tortuosity-contractures syndrome Benign:1

Benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Retinal arterial tortuosity;C2673195:Autosomal dominant familial hematuria-retinal arteriolar tortuosity-contractures syndrome;C3281105:Hemorrhage, intracerebral, susceptibility to;C4551998:Brain small vessel disease 1 with or without ocular anomalies;C5231411:Microangiopathy and leukoencephalopathy, pontine, autosomal dominant Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Aug 06, 2021

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.90
CADD	Benign	0.039
DANN	Benign	0.33

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

Publications

LitVar

Other links and lift over

dbSNP: rs188122235; hg19: chr13-110819495;