Total submissions: 2
| Submitter | RCV | SCV | Clinical significance | Condition | Last evaluated | Review status | Method | Comment |
|---|---|---|---|---|---|---|---|---|
| Gene |
RCV000486268 | SCV000570052 | uncertain significance | not provided | 2017-03-10 | criteria provided, single submitter | clinical testing | A variant of uncertain significance has been identified in the CHRNB2 gene. The A373T variant has not been published as a pathogenic variant, nor has it been reported as a benign variant to our knowledge. It was not observed in approximately 6,100 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project and was not observed with any significant frequency in the 1000 Genomes Project. The A373T variant is a non-conservative amino acid substitution, which is likely to impact secondary protein structure as these residues differ in polarity, charge, size and/or other properties. However, this substitution occurs at a position that is not conserved, and in silico analysis predicts this variant likely does not alter the protein structure/function. Additionally, this amino acid substitution is not predicted to occur within the transmembrane region of the protein, where the vast majority of pathogenic missense variants have been identified in association with epilepsy (Steinlein et al., 2010). Therefore, based on the currently available information, it is unclear whether this variant is a pathogenic variant or a rare benign variant. |
| Invitae | RCV001227485 | SCV001399846 | uncertain significance | Autosomal dominant nocturnal frontal lobe epilepsy | 2023-04-22 | criteria provided, single submitter | clinical testing | 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 CHRNB2 protein function. ClinVar contains an entry for this variant (Variation ID: 420992). This variant has not been reported in the literature in individuals affected with CHRNB2-related conditions. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 373 of the CHRNB2 protein (p.Ala373Thr). |