Malignant Hyperthermia, Susceptibility To, 5

A number sign (#) is used with this entry because susceptibility to malignant hyperthermia-5 (MHS5) is caused by heterozygous mutation in the CACNA1S gene (114208) on chromosome 1q32.

For a phenotypic description and a discussion of genetic heterogeneity of malignant hyperthermia, see MHS1 (145600).

Mapping

In a collaborative study in 3 pedigrees in Europe, in which disease status was classified according to the European in vitro contracture test (IVCT), Robinson et al. (1997) performed a genomewide screen and found that at least 2 further loci exist for MH susceptibility. One of these was located on 5p (601888). The other was located on 1q, between markers D1S422 and D1S1660. Between these 2 markers had already been localized a candidate gene, CACNL1A3 (CACNA1S; 114208), assigned to 1q32. This gene had been previously identified as the site of mutations causing hypokalemic periodic paralysis (170400). The MH family linked to 1q was from Grenoble, France.

Molecular Genetics

In affected members of a large French family with MHS, Monnier et al. (1997) identified a heterozygous mutation in the CACNA1S gene (114208.0004).