9-134817836-C-A

Position:

• chr9-134817836-C-A

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_000093.5(COL5A1):​c.4230+5C>A variant causes a splice donor 5th base, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000689 in 1,450,760 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: COL5A1 NM_000093.5 splice_donor_5th_base, intron
• Scores: Splicing: ADA: 0.00004448
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.609

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_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.85).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COL5A1	NM_000093.5	c.4230+5C>A		splice_donor_5th_base_variant, intron_variant		ENST00000371817.8	NP_000084.3
COL5A1	NM_001278074.1	c.4230+5C>A		splice_donor_5th_base_variant, intron_variant			NP_001265003.1
COL5A1	XM_017014266.3	c.4230+5C>A		splice_donor_5th_base_variant, intron_variant			XP_016869755.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
COL5A1	ENST00000371817.8	c.4230+5C>A		splice_donor_5th_base_variant, intron_variant		1	NM_000093.5	ENSP00000360882	P4
COL5A1	ENST00000371820.4	c.4230+5C>A		splice_donor_5th_base_variant, intron_variant		2		ENSP00000360885	A2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.89e-7 AC: 1 AN: 1450760 Hom.: 0 Cov.: 32 AF XY: 0.00000139 AC XY: 1 AN XY: 720628

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: 9.04e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000756

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

Aug 27, 2022

This variant is not present in population databases (gnomAD no frequency). This sequence change falls in intron 54 of the COL5A1 gene. It does not directly change the encoded amino acid sequence of the COL5A1 protein. It affects a nucleotide within the consensus splice site. This variant has not been reported in the literature in individuals affected with COL5A1-related conditions. 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. Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant is not likely to affect RNA splicing. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.85
CADD	Benign	0.15
DANN	Benign	0.51

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.000044
dbscSNV1_RF	Benign	0.062
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: rs142248898; hg19: chr9-137709682;