Total submissions: 3
Submitter | RCV | SCV | Clinical significance | Condition | Last evaluated | Review status | Method | Comment |
---|---|---|---|---|---|---|---|---|
Labcorp Genetics |
RCV002018472 | SCV002303152 | uncertain significance | Jeune thoracic dystrophy; Nephronophthisis | 2022-07-19 | criteria provided, single submitter | clinical testing | This sequence change replaces methionine, which is neutral and non-polar, with lysine, which is basic and polar, at codon 190 of the TTC21B protein (p.Met190Lys). 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 variant has not been reported in the literature in individuals affected with TTC21B-related conditions. ClinVar contains an entry for this variant (Variation ID: 1513727). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. 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. |
Ambry Genetics | RCV004970792 | SCV005523475 | uncertain significance | Inborn genetic diseases | 2024-07-02 | criteria provided, single submitter | clinical testing | The c.569T>A (p.M190K) alteration is located in exon 6 (coding exon 6) of the TTC21B gene. This alteration results from a T to A substitution at nucleotide position 569, causing the methionine (M) at amino acid position 190 to be replaced by a lysine (K). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. |
Prevention |
RCV004734399 | SCV005344806 | uncertain significance | TTC21B-related disorder | 2024-08-16 | no assertion criteria provided | clinical testing | The TTC21B c.569T>A variant is predicted to result in the amino acid substitution p.Met190Lys. To our knowledge, this variant has not been reported in the literature. This variant is reported in 0.0018% of alleles in individuals of European (Non-Finnish) descent in gnomAD. At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. |