ORPHA: 101016, 768; DO: 0110652;
Location | Phenotype |
Phenotype MIM number |
Inheritance |
Phenotype mapping key |
Gene/Locus |
Gene/Locus MIM number |
---|---|---|---|---|---|---|
7q21.2 | ?Long QT syndrome 11 | 611820 | Autosomal dominant | 3 | AKAP9 | 604001 |
A number sign (#) is used with this entry because of evidence that long QT syndrome-11 (LQT11) is caused by heterozygous mutation in the gene encoding the A-kinase anchor protein-9 (AKAP9; 604001) on chromosome 7q21. One such family has been reported.
For a discussion of genetic heterogeneity of long QT syndrome, see LQT1 (192500).
Congenital long QT syndrome is electrocardiographically characterized by a prolonged QT interval and polymorphic ventricular arrhythmias (torsade de pointes). These cardiac arrhythmias may result in recurrent syncope, seizure, or sudden death (Jongbloed et al., 1999).
In a 13-year-old Caucasian girl with long QT syndrome, who was negative for mutation in the known LQT genes, Chen et al. (2007) identified heterozygosity for a ser1570-to-leu (S1570L; 604001.0001) substitution in the AKAP9 gene. The patient's father and 2 sisters had also ECG-diagnosed LQT syndrome; 1 affected sister, with a QTc of 480ms, agreed to testing and was found to carry the mutation, which was not found in 1,320 reference alleles.
Chen, L., Marquardt, M. L., Tester, D. J., Sampson, K. J., Ackerman, M. J., Kass, R. S. Mutation of an A-kinase-anchoring protein causes long-QT syndrome. Proc. Nat. Acad. Sci. 104: 20990-20995, 2007. [PubMed: 18093912] [Full Text: https://doi.org/10.1073/pnas.0710527105]
Jongbloed, R. J. E., Wilde, A. A. M., Geelen, J. L. M. C., Doevendans, P., Schaap, C., Van Langen, I., van Tintelen, J. P., Cobben, J. M., Beaufort-Krol, G. C. M., Geraedts, J. P. M., Smeets, H. J. M. Novel KCNQ1 and HERG missense mutations in Dutch long-QT families. Hum. Mutat. 13: 301-310, 1999. [PubMed: 10220144] [Full Text: https://doi.org/10.1002/(SICI)1098-1004(1999)13:4<301::AID-HUMU7>3.0.CO;2-V]