7-94408810-C-T

Position:

• chr7-94408810-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP2

The NM_000089.4(COL1A2):​c.779C>T​(p.Ala260Val) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: COL1A2 NM_000089.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 4.91

Genes affected

COL1A2 (HGNC:2198): (collagen type I alpha 2 chain) This gene encodes the pro-alpha2 chain of type I collagen whose triple helix comprises two alpha1 chains and one alpha2 chain. Type I is a fibril-forming collagen found in most connective tissues and is abundant in bone, cornea, dermis and tendon. Mutations in this gene are associated with osteogenesis imperfecta types I-IV, Ehlers-Danlos syndrome type VIIB, recessive Ehlers-Danlos syndrome Classical type, idiopathic osteoporosis, and atypical Marfan syndrome. Symptoms associated with mutations in this gene, however, tend to be less severe than mutations in the gene for the alpha1 chain of type I collagen (COL1A1) reflecting the different role of alpha2 chains in matrix integrity. Three transcripts, resulting from the use of alternate polyadenylation signals, have been identified for this gene. [provided by R. Dalgleish, Feb 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), COL1A2. . Gene score misZ 2.1491 (greater than the threshold 3.09). Trascript score misZ 3.5344 (greater than threshold 3.09). GenCC has associacion of gene with Ehlers-Danlos/osteogenesis imperfecta syndrome, Ehlers-Danlos syndrome, cardiac valvular type, ehlers-danlos syndrome, arthrochalasia type, 2, Ehlers-Danlos syndrome, arthrochalasia type, osteogenesis imperfecta type 3, high bone mass osteogenesis imperfecta, combined osteogenesis imperfecta and Ehlers-Danlos syndrome 2, osteogenesis imperfecta type 4, osteogenesis imperfecta type 2, osteogenesis imperfecta type 1.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COL1A2	NM_000089.4	c.779C>T	p.Ala260Val	missense_variant	16/52	ENST00000297268.11	NP_000080.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
COL1A2	ENST00000297268.11	c.779C>T	p.Ala260Val	missense_variant	16/52	1	NM_000089.4	ENSP00000297268.6

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Osteogenesis imperfecta type I;C0268335:Ehlers-Danlos syndrome, classic type, 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 09, 2022

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) performed at Invitae indicates that this missense variant is not expected to disrupt COL1A2 protein function. ClinVar contains an entry for this variant (Variation ID: 547237). This variant has not been reported in the literature in individuals affected with COL1A2-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 260 of the COL1A2 protein (p.Ala260Val). -

Connective tissue disorder Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Center for Human Genetics, Inc, Center for Human Genetics, Inc

Nov 01, 2016

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.10
BayesDel_addAF	Uncertain	0.15	D
BayesDel_noAF	Uncertain	-0.030
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.66	D;.
Eigen	Uncertain	0.49
Eigen_PC	Uncertain	0.58
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.93	D;D
M_CAP	Benign	0.076	D
MetaRNN	Uncertain	0.57	D;D
MetaSVM	Uncertain	0.59	D
MutationAssessor	Benign	1.3	L;.
PrimateAI	Uncertain	0.52	T
PROVEAN	Uncertain	-2.6	D;.
REVEL	Uncertain	0.50
Sift	Benign	0.053	T;.
Sift4G	Benign	0.22	T;T
Polyphen		0.84	P;.
Vest4		0.53
MutPred		0.45		Gain of catalytic residue at A260 (P = 0.1065);.;
MVP		0.64
MPC		0.26
ClinPred		0.94	D
GERP RS		5.7
Varity_R		0.19
gMVP		0.61

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: rs1554395967; hg19: chr7-94038122;