rs1396856908

chr7-94416420-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM1 PP2

The NM_000089.4(COL1A2):c.1780C>G(p.Pro594Ala) variant causes a missense change. The variant allele was found at a frequency of 0.00000696 in 1,579,560 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000070 (0 hom.)
• Consequence: COL1A2 NM_000089.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.92

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.

• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 3 uncertain in NM_000089.4
• PP2: Missense variant where missense usually causes diseases, COL1A2

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
COL1A2	NM_000089.4	c.1780C>G	p.Pro594Ala	missense_variant	31/52	ENST00000297268.11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
COL1A2	ENST00000297268.11	c.1780C>G	p.Pro594Ala	missense_variant	31/52	1	NM_000089.4	P1
COL1A2	ENST00000473573.5	n.117C>G		non_coding_transcript_exon_variant	3/11	2
COL1A2	ENST00000488298.5	n.204C>G		non_coding_transcript_exon_variant	5/5	2

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152142 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000701 AC: 10 AN: 1427418 Hom.: 0 Cov.: 30 AF XY: 0.00000708 AC XY: 5 AN XY: 706464

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: 0.00000914

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152142 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74328

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000282 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

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

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Oct 07, 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: 526890). This missense change has been observed in individual(s) with clinical features of COL1A2-related conditions (Invitae). This variant is not present in population databases (gnomAD no frequency). This sequence change replaces proline, which is neutral and non-polar, with alanine, which is neutral and non-polar, at codon 594 of the COL1A2 protein (p.Pro594Ala). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.047
BayesDel_addAF	Pathogenic	0.21	D
BayesDel_noAF	Uncertain	0.060
Cadd	Uncertain	24
Dann	Uncertain	0.99
DEOGEN2	Uncertain	0.79	D;.
Eigen	Uncertain	0.45
Eigen_PC	Uncertain	0.52
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.94	D;D
M_CAP	Uncertain	0.23	D
MetaRNN	Uncertain	0.56	D;D
MetaSVM	Pathogenic	0.97	D
MutationAssessor	Benign	1.6	L;.
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.57	T
PROVEAN	Pathogenic	-6.4	D;.
REVEL	Uncertain	0.57
Sift	Uncertain	0.019	D;.
Sift4G	Uncertain	0.0030	D;D
Polyphen		0.56	P;.
Vest4		0.42
MutPred		0.38		Loss of catalytic residue at P593 (P = 0.0144);.;
MVP		0.72
MPC		0.20
ClinPred		0.90	D
GERP RS		5.3
Varity_R		0.25
gMVP		0.80

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs1396856908; hg19: chr7-94045732;