Total submissions: 2
Submitter | RCV | SCV | Clinical significance | Condition | Last evaluated | Review status | Method | Comment |
---|---|---|---|---|---|---|---|---|
Gene |
RCV000181804 | SCV000234107 | pathogenic | not provided | 2014-02-05 | criteria provided, single submitter | clinical testing | p.Leu559Phe (CTC>TTC): c.1675 C>T in exon 7 of the KCNH2 gene (NM_000238.2)While the L559F mutation in the KCNH2 gene has not been reported to our knowledge, a mutation affecting this same residue, L559H, has been reported in association with LQTS (Liu et al., 2002). Additionally, mutations in nearby residues (A558E, A558P, A561P, A561T, A561V) have been reported in association with LQTS, further supporting the functional importance of this residue and this region of the protein. L559F results in a conservative amino acid substitution as these residues share similar properties, and are least likely to impact secondary structure. The L559F residue is completely conserved across species and in silico analysis predicts L559F is damaging to the protein structure/function. Furthermore, L559F was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations.In summary, L559F in the KCNH2 gene is interpreted as a likely disease-causing mutation. The variant is found in LQT panel(s). |
Ambry Genetics | RCV002399646 | SCV002714392 | uncertain significance | Cardiovascular phenotype | 2020-12-08 | criteria provided, single submitter | clinical testing | The p.L559F variant (also known as c.1675C>T), located in coding exon 7 of the KCNH2 gene, results from a C to T substitution at nucleotide position 1675. The leucine at codon 559 is replaced by phenylalanine, an amino acid with highly similar properties, and is located in the S5 domain. This alteration has been reported in a long QT syndrome (LQTS) cohort (Itoh H et al. Eur Heart J, 2016 May;37:1456-64). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. |