9-134758287-G-T

Position:

• chr9-134758287-G-T

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1 PM2 PP2 PP3_Moderate

The NM_000093.5(COL5A1):​c.1926G>T​(p.Lys642Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,820 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 (★).

• 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: 0.364

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 Likely_pathogenic. Variant got 7 ACMG points.

• PM1: In a modified_residue 5-hydroxylysine (size 0) in uniprot entity CO5A1_HUMAN
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), COL5A1. . Gene score misZ 2.0682 (greater than the threshold 3.09). Trascript score misZ 4.1823 (greater than threshold 3.09). GenCC has associacion of gene with Ehlers-Danlos syndrome, classic type, 1, arterial disorder, Ehlers-Danlos syndrome, classic type.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.862

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COL5A1	NM_000093.5	c.1926G>T	p.Lys642Asn	missense_variant	18/66	ENST00000371817.8	NP_000084.3
COL5A1	NM_001278074.1	c.1926G>T	p.Lys642Asn	missense_variant	18/66		NP_001265003.1
COL5A1	XM_017014266.3	c.1926G>T	p.Lys642Asn	missense_variant	18/65		XP_016869755.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
COL5A1	ENST00000371817.8	c.1926G>T	p.Lys642Asn	missense_variant	18/66	1	NM_000093.5	ENSP00000360882.3
COL5A1	ENST00000371820.4	c.1926G>T	p.Lys642Asn	missense_variant	18/66	2		ENSP00000360885.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461820 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727224

Gnomad4 AFR exome AF: 0.0000299

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.: 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

Labcorp Genetics (formerly Invitae), Labcorp

Jun 18, 2023

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. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on COL5A1 protein function. ClinVar contains an entry for this variant (Variation ID: 529276). This missense change has been observed in individual(s) with clinical features of COL5A1-related conditions (Invitae). This variant is not present in population databases (gnomAD no frequency). This sequence change replaces lysine, which is basic and polar, with asparagine, which is neutral and polar, at codon 642 of the COL5A1 protein (p.Lys642Asn). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.96
BayesDel_addAF	Uncertain	0.11	D
BayesDel_noAF	Uncertain	-0.080
CADD	Benign	21
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.66	D;.
Eigen	Uncertain	0.27
Eigen_PC	Benign	0.19
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Benign	0.81	T;T
M_CAP	Pathogenic	0.66	D
MetaRNN	Pathogenic	0.86	D;D
MetaSVM	Uncertain	0.71	D
MutationAssessor	Benign	1.3	L;L
PrimateAI	Pathogenic	0.86	D
PROVEAN	Pathogenic	-4.4	D;.
REVEL	Pathogenic	0.72
Sift	Uncertain	0.0010	D;.
Sift4G	Pathogenic	0.0010	D;D
Polyphen		1.0	D;.
Vest4		0.76
MutPred		0.52		Loss of glycosylation at K642 (P = 0.0025);Loss of glycosylation at K642 (P = 0.0025);
MVP		0.83
MPC		1.6
ClinPred		0.99	D
GERP RS		3.6
Varity_R		0.72
gMVP		0.93

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: rs918992441; hg19: chr9-137650133;