chr2-227279793-G-A

Variant names:

• chr2-227279793-G-A
• rs1553759430
• NM_000091.5:c.2126G>A

Variant summary

Our verdict is Pathogenic. The variant received 13 ACMG points: 13P and 0B. PM1 PM2 PP3 PP5_Very_Strong

The NM_000091.5(COL4A3):​c.2126G>A​(p.Gly709Glu) variant causes a missense, splice region change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. G709G) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: COL4A3 NM_000091.5 missense, splice_region
• Scores: Splicing: ADA: 0.9992
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 4.47
• 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 13 ACMG points.

• PM1: In a hotspot region, there are 2 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
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. Scorers claiming Uncertain: max_spliceai. No scorers claiming Benign.
• PP5: Variant 2-227279793-G-A is Pathogenic according to our data. Variant chr2-227279793-G-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 447168.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

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

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	COL4A3	NM_000091.5	MANE Select	c.2126G>A	p.Gly709Glu	missense splice_region	Exon 29 of 52	NP_000082.2
	MFF-DT	NR_102371.1		n.330-218C>T		intron	N/A

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	COL4A3	ENST00000396578.8	TSL:1 MANE Select	c.2126G>A	p.Gly709Glu	missense splice_region	Exon 29 of 52	ENSP00000379823.3
	MFF-DT	ENST00000439598.6	TSL:1	n.330-218C>T		intron	N/A
	MFF-DT	ENST00000396588.6	TSL:2	n.484-215C>T		intron	N/A

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 29

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hematuria, benign familial, 2;C5882663:Autosomal dominant Alport syndrome;C5882699:Alport syndrome 3b, autosomal recessive Pathogenic:1

Apr 08, 2024

Fulgent Genetics, Fulgent Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

not provided Pathogenic:1

Jun 01, 2017

Athena Diagnostics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Autosomal dominant Alport syndrome Pathogenic:1

Feb 01, 2020

Molecular Biology Laboratory, Fundació Puigvert

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: research

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.89
BayesDel_addAF	Pathogenic	0.54	D
BayesDel_noAF	Pathogenic	0.54
CADD	Pathogenic	33
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.68	D
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.92
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Pathogenic	0.81	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	4.5	H
PhyloP100		4.5
PrimateAI	Uncertain	0.74	T
PROVEAN	Pathogenic	-6.9	D
REVEL	Pathogenic	0.99
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.97
MutPred		0.98		Gain of solvent accessibility (P = 0.0012)
MVP		0.95
MPC		0.25
ClinPred		1.0	D
GERP RS		6.0
Varity_R		0.98
gMVP		0.99
Mutation Taster		=3/97	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.82
SpliceAI score (max)		0.30		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.30		Position offset: 3

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

Other links and lift over

dbSNP: rs1553759430; hg19: chr2-228144509;