rs104886158

chrX-108601885-G-A

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1 PM5 PP3 PP5_Moderate

The NM_033380.3(COL4A5):c.2042G>A(p.Gly681Asp) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. In-silico tool predicts a pathogenic outcome for this variant. 13/22 in silico tools predict a damaging outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★). Another nucleotide change resulting in same amino acid change has been previously reported as Likely pathogenicin UniProt. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G681S) has been classified as Pathogenic.

• Frequency:
  • Genomes: not found (cov: 22)
  • Exomes 𝑓: 0.0 (0 hom. 0 hem.)
  • Failed GnomAD Quality Control
• Consequence: COL4A5 NM_033380.3 missense, splice_region
• Scores: Splicing: ADA: 0.9918
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 9.26

Genes affected

COL4A5 (HGNC:2207): (collagen type IV alpha 5 chain) This gene encodes one of the six subunits of type IV collagen, the major structural component of basement membranes. Mutations in this gene are associated with X-linked Alport syndrome, also known as hereditary nephritis. 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. Alternatively spliced transcript variants have been identified for this gene. [provided by RefSeq, Aug 2010]

ACMG classification

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 2 uncertain in NM_033380.3
• PM5: Other missense variant is known to change same aminoacid residue: Variant chrX-108601485-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 840783.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. Scorers claiming Benign: max_spliceai.
• PP5: Variant X-108601885-G-A is Pathogenic according to our data. Variant chrX-108601885-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 2138701.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chrX-108601885-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
COL4A5	NM_033380.3	c.2042G>A	p.Gly681Asp	missense_variant, splice_region_variant	27/53	ENST00000328300.11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
COL4A5	ENST00000328300.11	c.2042G>A	p.Gly681Asp	missense_variant, splice_region_variant	27/53	1	NM_033380.3
COL4A5	ENST00000483338.1	c.866G>A	p.Gly289Asp	missense_variant, splice_region_variant	11/20	1
COL4A5	ENST00000361603.7	c.2042G>A	p.Gly681Asp	missense_variant, splice_region_variant	27/51	2		P1

Frequencies

GnomAD3 genomes Cov.: 22

GnomAD4 exome Data not reliable, filtered out with message: AC0;AS_VQSR AF: 0.00 AC: 0 AN: 997540 Hom.: 0 Cov.: 19 AF XY: 0.00 AC XY: 0 AN XY: 299576

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 22

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Invitae

Mar 20, 2022

For these reasons, this variant has been classified as Pathogenic. This variant disrupts the triple helix domain of COL4A5. Glycine residues within the Gly-Xaa-Yaa repeats of the triple helix domain are required for the structure and stability of fibrillar collagens (PMID: 7695699, 8218237, 19344236). In COL4A5, missense variants at these glycine residues are significantly enriched in individuals with disease (PMID: 23720012, 27627812) compared to the general population (ExAC). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Not Available"; Align-GVGD: "Class C0"). This missense change has been observed in individuals with Alport syndrome (PMID: 8940267, 28658201, 33040356). This variant is not present in population databases (gnomAD no frequency). This sequence change replaces glycine, which is neutral and non-polar, with aspartic acid, which is acidic and polar, at codon 681 of the COL4A5 protein (p.Gly681Asp). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.74	D
BayesDel_noAF	Pathogenic	0.83
Cadd	Pathogenic	29
Dann	Uncertain	1.0
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Uncertain	0.90	D;D;D
M_CAP	Pathogenic	0.98	D
MetaRNN	Pathogenic	0.99	D;D;D
MetaSVM	Pathogenic	0.95	D
MutationAssessor	Pathogenic	4.6	H;H;.
MutationTaster	Benign	1.0	A;A
PrimateAI	Pathogenic	0.85	D
PROVEAN	Pathogenic	-5.9	D;D;.
REVEL	Pathogenic	0.99
Sift	Pathogenic	0.0	D;D;.
Sift4G	Pathogenic	0.0	D;D;.
Polyphen		1.0	.;D;D
Vest4		0.94
MutPred		1.0		Gain of solvent accessibility (P = 0.039);Gain of solvent accessibility (P = 0.039);.;
MVP		1.0
MPC		0.39
ClinPred		1.0	D
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		1.0
gMVP		1.0

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	0.99
dbscSNV1_RF	Pathogenic	0.76
SpliceAI score (max)		0.010		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: rs104886158; hg19: chrX-107845115;