rs377592935

Positions:

• chr13-110172777-G-C

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.3506-7C>G variant causes a splice region, splice polypyrimidine tract, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000674 in 1,613,638 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.0010 (0 hom., cov: 33)
  • Exomes 𝑓: 0.00064 (1 hom.)
• Consequence: COL4A1 NM_001845.6 splice_region, splice_polypyrimidine_tract, intron
• Scores: Splicing: ADA: 0.003082
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:8
• Conservation: PhyloP100: 1.00

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=-0.81).
• BP6: Variant 13-110172777-G-C is Benign according to our data. Variant chr13-110172777-G-C is described in ClinVar as [Likely_benign]. Clinvar id is 311038.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BS1: Variant frequency is greater than expected in population nfe. gnomad4 allele frequency = 0.00104 (158/152368) while in subpopulation NFE AF= 0.00176 (120/68040). AF 95% confidence interval is 0.00151. There are 0 homozygotes in gnomad4. There are 84 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck.
• BS2: High AC in GnomAd4 at 158 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
COL4A1	NM_001845.6	c.3506-7C>G		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		ENST00000375820.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
COL4A1	ENST00000375820.10	c.3506-7C>G		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		1	NM_001845.6	P1

Frequencies

GnomAD3 genomes AF: 0.00104 AC: 158 AN: 152250 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000723

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000131

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00301

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00176

Gnomad OTH AF: 0.000478

GnomAD3 exomes AF: 0.000787 AC: 198 AN: 251472 Hom.: 1 AF XY: 0.000831 AC XY: 113 AN XY: 135912

Gnomad AFR exome AF: 0.000185

Gnomad AMR exome AF: 0.0000867

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00351

Gnomad NFE exome AF: 0.000914

Gnomad OTH exome AF: 0.00195

GnomAD4 exome AF: 0.000636 AC: 929 AN: 1461270 Hom.: 1 Cov.: 31 AF XY: 0.000671 AC XY: 488 AN XY: 727014

Gnomad4 AFR exome AF: 0.000120

Gnomad4 AMR exome AF: 0.0000895

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00401

Gnomad4 NFE exome AF: 0.000596

Gnomad4 OTH exome AF: 0.000745

GnomAD4 genome AF: 0.00104 AC: 158 AN: 152368 Hom.: 0 Cov.: 33 AF XY: 0.00113 AC XY: 84 AN XY: 74514

Gnomad4 AFR AF: 0.0000721

Gnomad4 AMR AF: 0.000131

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00301

Gnomad4 NFE AF: 0.00176

Gnomad4 OTH AF: 0.000473

Alfa AF: 0.00185 Hom.: 0

Bravo AF: 0.000382

EpiCase AF: 0.000818

EpiControl AF: 0.000296

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 29, 2024	- -
Benign, criteria provided, single submitter	clinical testing	Athena Diagnostics	Dec 19, 2017	- -
Likely benign, criteria provided, single submitter	clinical testing	GeneDx	Dec 02, 2020	- -
Likely benign, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Dec 01, 2023	COL4A1: BP4, BS1 -

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

Benign, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 12, 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 12, 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

Benign, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Aug 16, 2021

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.81
CADD	Benign	4.3
DANN	Benign	0.42

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.0031
dbscSNV1_RF	Benign	0.21
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: rs377592935; hg19: chr13-110825124;