Total submissions: 1
Submitter | RCV | SCV | Clinical significance | Condition | Last evaluated | Review status | Method | Comment |
---|---|---|---|---|---|---|---|---|
Labcorp Genetics |
RCV001969058 | SCV002252082 | likely pathogenic | Osteogenesis imperfecta type I; Ehlers-Danlos syndrome, classic type, 1 | 2021-08-29 | criteria provided, single submitter | clinical testing | This variant has not been reported in the literature in individuals affected with COL1A2-related conditions. This sequence change replaces glycine with alanine at codon 625 of the COL1A2 protein (p.Gly625Ala). The glycine residue is highly conserved and there is a small physicochemical difference between glycine and alanine. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the ExAC database. 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 expected to disrupt COL1A2 protein function. This variant disrupts the triple helix domain of COL1A2. Glycine residues within the Gly-Xaa-Yaa repeats of the triple helix domain are required for the structure and stability of fibrillar collagens (PMID: 7695699, 8218237, 19344236). In COL1A2, variants affecting these glycine residues are significantly enriched in individuals with disease (PMID: 9016532, 17078022) compared to the general population (ExAC). In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. |