rs1554787531

Positions:

• chr9-134727279-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM2 PP2 PP3_Moderate

The NM_000093.5(COL5A1):​c.668A>G​(p.Gln223Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,738 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Q223P) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: COL5A1 NM_000093.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.84

Genes affected

COL5A1 (HGNC:2209): (collagen type V alpha 1 chain) This gene encodes an alpha chain for one of the low abundance fibrillar collagens. Fibrillar collagen molecules are trimers that can be composed of one or more types of alpha chains. Type V collagen is found in tissues containing type I collagen and appears to regulate the assembly of heterotypic fibers composed of both type I and type V collagen. This gene product is closely related to type XI collagen and it is possible that the collagen chains of types V and XI constitute a single collagen type with tissue-specific chain combinations. The encoded procollagen protein occurs commonly as the heterotrimer pro-alpha1(V)-pro-alpha1(V)-pro-alpha2(V). Mutations in this gene are associated with Ehlers-Danlos syndrome, types I and II. Alternative splicing of this gene results in multiple transcript variants. [provided by RefSeq, May 2013]

ACMG classification

Verdict is Uncertain_significance. Variant got 5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, COL5A1
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.872

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
COL5A1	NM_000093.5	c.668A>G	p.Gln223Arg	missense_variant	5/66	ENST00000371817.8
COL5A1	NM_001278074.1	c.668A>G	p.Gln223Arg	missense_variant	5/66
COL5A1	XM_017014266.3	c.668A>G	p.Gln223Arg	missense_variant	5/65

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
COL5A1	ENST00000371817.8	c.668A>G	p.Gln223Arg	missense_variant	5/66	1	NM_000093.5	P4
COL5A1	ENST00000371820.4	c.668A>G	p.Gln223Arg	missense_variant	5/66	2		A2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461738 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727180

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: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Ehlers-Danlos syndrome, classic type, 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Nov 23, 2017

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals with COL5A1-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces glutamine with arginine at codon 223 of the COL5A1 protein (p.Gln223Arg). The glutamine residue is moderately conserved and there is a small physicochemical difference between glutamine and arginine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.69
BayesDel_addAF	Pathogenic	0.27	D
BayesDel_noAF	Pathogenic	0.15
CADD	Uncertain	25
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.59	D;.
Eigen	Uncertain	0.63
Eigen_PC	Uncertain	0.56
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.95	D;D
M_CAP	Uncertain	0.17	D
MetaRNN	Pathogenic	0.87	D;D
MetaSVM	Uncertain	0.19	D
MutationAssessor	Uncertain	2.2	M;M
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.65	T
PROVEAN	Uncertain	-3.0	D;.
REVEL	Pathogenic	0.77
Sift	Benign	0.090	T;.
Sift4G	Uncertain	0.025	D;D
Polyphen		0.98	D;.
Vest4		0.92
MutPred		0.59		Gain of sheet (P = 0.0827);Gain of sheet (P = 0.0827);
MVP		0.92
MPC		0.66
ClinPred		0.99	D
GERP RS		4.2
Varity_R		0.26
gMVP		0.53

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

Publications

LitVar

Other links and lift over

dbSNP: rs1554787531; hg19: chr9-137619125;