7-94426459-G-C

Variant names:

• chr7-94426459-G-C
• rs72659319
• NM_000089.4:c.3034G>C

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PM2 PM5 PP2 PP3_Strong PP5_Moderate

The NM_000089.4(COL1A2):​c.3034G>C​(p.Gly1012Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G1012C) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: COL1A2 NM_000089.4 missense
• Clinical Significance: Pathogenic criteria provided, single submitter P:2
• Conservation: PhyloP100: 10.0

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 Pathogenic. Variant got 11 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr7-94426459-G-T is described in Lovd as [Pathogenic].
• PP2: Missense variant in the COL1A2 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 437 curated pathogenic missense variants (we use a threshold of 10). The gene has 17 curated benign missense variants. Gene score misZ: 2.1491 (below the threshold of 3.09). Trascript score misZ: 3.5344 (above the threshold of 3.09). GenCC associations: The gene is linked to 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.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.994
• PP5: Variant 7-94426459-G-C is Pathogenic according to our data. Variant chr7-94426459-G-C is described in ClinVar as [Pathogenic]. Clinvar id is 17235.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
COL1A2	NM_000089.4	c.3034G>C	p.Gly1012Arg	missense_variant	Exon 46 of 52	ENST00000297268.11	NP_000080.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
COL1A2	ENST00000297268.11	c.3034G>C	p.Gly1012Arg	missense_variant	Exon 46 of 52	1	NM_000089.4	ENSP00000297268.6
COL1A2	ENST00000478215.1	n.593G>C		non_coding_transcript_exon_variant	Exon 4 of 4	3
COL1A2	ENST00000481570.5	n.3007G>C		non_coding_transcript_exon_variant	Exon 5 of 8	2
COL1A2	ENST00000488121.1	n.-51G>C		upstream_gene_variant		2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, single submitter

Submissions by phenotype

Osteogenesis imperfecta with normal sclerae, dominant form Pathogenic:1

Jan 15, 1993

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

not provided Pathogenic:1

May 16, 2016

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The G1012R pathogenic variant in the COL1A2 gene has been reported previously in the heterozygous state in association with osteogenesis imperfecta (Roschger et al., 2008; Wenstrup et al., 1998). Functional studies demonstrate that this variant disrupts a Gly-X-Y triplet in the triple helical domain of the COL1A2 protein and produces abnormal collagen molecules, resulting in aberrant accumulation and organization of collagen fibers (Wenstrup et al., 1988). The G1012R variant was not observed in approximately 6500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. This variant is a non-conservative amino acid substitution and occurs at a position that is conserved across species. A missense variant in the same residue (G1012S) has been reported in the Human Gene Mutation Database in association with osteogenesis imperfecta (Stenson et al., 2014), supporting the functional importance of this residue of the protein. We interpret G1012R as a pathogenic variant -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.59	D
BayesDel_noAF	Pathogenic	0.61
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.80	D;.
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.96
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.99	D;D
M_CAP	Pathogenic	0.92	D
MetaRNN	Pathogenic	0.99	D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	4.2	H;.
PrimateAI	Pathogenic	0.82	D
PROVEAN	Pathogenic	-7.1	D;.
REVEL	Pathogenic	0.96
Sift	Pathogenic	0.0	D;.
Sift4G	Pathogenic	0.0010	D;D
Polyphen		1.0	D;.
Vest4		0.91
MutPred		0.99		Gain of MoRF binding (P = 0.029);.;
MVP		0.99
MPC		0.25
ClinPred		1.0	D
GERP RS		5.8
Varity_R		0.92
gMVP		1.0

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: rs72659319; hg19: chr7-94055771;