rs995895784

Positions:

• chr9-134642222-C-A
• chr9-134642222-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 3P and 2B. PM2 PP2 BP4_Moderate

The NM_000093.5(COL5A1):​c.35C>A​(p.Ala12Glu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign 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. A12T) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: COL5A1 NM_000093.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.321

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 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, COL5A1
• BP4: Computational evidence support a benign effect (MetaRNN=0.12523317).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
COL5A1	NM_000093.5	c.35C>A	p.Ala12Glu	missense_variant	1/66	ENST00000371817.8
COL5A1	NM_001278074.1	c.35C>A	p.Ala12Glu	missense_variant	1/66
COL5A1	XM_017014266.3	c.35C>A	p.Ala12Glu	missense_variant	1/65

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
COL5A1	ENST00000371817.8	c.35C>A	p.Ala12Glu	missense_variant	1/66	1	NM_000093.5	P4
COL5A1	ENST00000371820.4	c.35C>A	p.Ala12Glu	missense_variant	1/66	2		A2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1149430 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 558472

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.: 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

Aug 13, 2021

This sequence change replaces alanine with glutamic acid at codon 12 of the COL5A1 protein (p.Ala12Glu). The alanine residue is weakly conserved and there is a moderate physicochemical difference between alanine and glutamic acid. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate insufficient coverage at this position in the ExAC database. This missense change has been observed in individual(s) with clinical features of COL5A1-related conditions (Invitae). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.25
BayesDel_addAF	Benign	-0.048	T
BayesDel_noAF	Benign	-0.31
CADD	Benign	17
DANN	Uncertain	0.98
DEOGEN2	Benign	0.093	T;.
Eigen	Benign	-0.80
Eigen_PC	Benign	-0.75
FATHMM_MKL	Benign	0.044	N
LIST_S2	Benign	0.27	T;T
M_CAP	Pathogenic	0.62	D
MetaRNN	Benign	0.13	T;T
MetaSVM	Benign	-0.60	T
MutationAssessor	Benign	0.0	N;N
MutationTaster	Benign	1.0	N
PrimateAI	Pathogenic	0.83	D
PROVEAN	Benign	0.46	N;.
REVEL	Benign	0.16
Sift	Benign	0.079	T;.
Sift4G	Benign	0.099	T;T
Polyphen		0.0	B;.
Vest4		0.085
MutPred		0.44		Loss of MoRF binding (P = 0.0421);Loss of MoRF binding (P = 0.0421);
MVP		0.29
MPC		0.23
ClinPred		0.16	T
GERP RS		0.35
Varity_R		0.058
gMVP		0.28

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: rs995895784; hg19: chr9-137534068;