This report describes cardiomyopathy, familial hypertrophic 17 (CMH17); CMH17 exhibits autosomal recessive inheritance. The human gene implicated in this disease JPH3, one of four junctophilin genes in human. The single junctophilin gene in Drosophila, jp, has been used to model diseases caused by this gene family; see the report for 'neuromuscular disease, JPH-related' (FBhh0000819) for information on experimental results in flies relevant to CMH17 and other JPH-related diseases.
[updated Jun. 2018 by FlyBase; FBrf0222196]
Familial hypertrophic cardiomyopathy is a heart condition characterized by thickening (hypertrophy) of cardiac muscle. Thickening usually occurs in the interventricular septum, the muscular wall that separates the left ventricle from the right ventricle. Cardiac hypertrophy often begins in adolescence or young adulthood, although it can develop at any time throughout life. The symptoms are variable, even within the same family. While most people this condition are symptom-free or have only mild symptoms, hypertrophic cardiomyopathy can cause abnormal heart rhythms (arrhythmias) that may be life threatening. People with familial hypertrophic cardiomyopathy have an increased risk of sudden death, even if they have no other symptoms of the condition. A small number of affected individuals develop potentially fatal heart failure, which may require heart transplantation. [from Genetics Home Reference, familial hypertrophic cardiomyopathy; 2016.10.13]
Hypertrophic cardiomyopathy in early stages produces a presystolic gallop due to an atrial heart sound, and EKG changes of ventricular hypertrophy. Progressive ventricular outflow obstruction may cause palpitation associated with arrhythmia, congestive heart failure, and sudden death. Hypertrophic cardiomyopathy accounts for a significant number (exceeding 25% in one study) of sudden deaths of young athletes. [from MIM:192600; 2016.10.28]
[CARDIOMYOPATHY, FAMILIAL HYPERTROPHIC, 17; CMH17](https://omim.org/entry/613873)
[JUNCTOPHILIN 2; JPH2](https://omim.org/entry/605267)
Hypertrophic cardiomyopathy-17 can be caused by heterozygous mutation in the junctophilin gene (JPH2). [from MIM:613873; 2018.06.21]
The JPH2 gene encodes junctophilin-3, a member of a conserved family of proteins that are components of junctional complexes. Junctional complexes between the plasma membrane (PM) and endoplasmic/sarcoplasmic reticulum (ER/SR) are a common feature of all excitable cell types and mediate cross talk between cell surface and intracellular ion channels (Takeshima et al. 2000; pubmed:10949023). [from MIM:613873; 2018.06.21]
