Exclusion of defects in the skeletal muscle specific regions of the DHPR alpha 1 subunit as frequent causes of malignant hyperthermia.
The molecular defect predisposing to the majority of malignant hyperthermia (MH) cases is unknown, although various point mutations in the ryanodine receptor gene (RYR1) have been associated with susceptibility in a small proportion of cases. We report here that one of these, the Arg163Cys substitution, does not cosegregate with MH susceptibility. Comparison of cDNA sequences encoding the skeletal muscle specific components of the dihydropyridine receptor alpha 1 subunit between MH susceptible (MHS) and MH non-susceptible (MHN) patients was made in subjects without the reported MH linked RYR1 mutations. There were no differences within the sequence encoding the II-III loop or the IS3/IS3-IS4 segment, excluding defects in these functional segments of the alpha 1 subunit as frequent causes of MH.
O'Brien
R O
RO
Division of Biochemistry and Molecular Biology, John Curtin School of Medical Research, Australian National University, Canberra, Australia.
Taske
N L
NL
Hansbro
P M
PM
Matthaei
K I
KI
Hogan
S P
SP
Denborough
M A
MA
Foster
P S
PS
D001483:Base Sequence; D002118:Calcium / Q000378:metabolism; D015220:Calcium Channels / Q000737:chemistry / Q000235:genetics*; D020746:Calcium Channels, L-Type; D018076:DNA, Complementary / Q000235:genetics; D005260:Female; D018740:Genetic Heterogeneity; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D008305:Malignant Hyperthermia / Q000235:genetics*; D008969:Molecular Sequence Data; D009124:Muscle Proteins / Q000235:genetics*; D010375:Pedigree; D017354:Point Mutation; D019837:Ryanodine Receptor Calcium Release Channel; D012519:Sarcoplasmic Reticulum / Q000378:metabolism
D015220:Calcium Channels; D020746:Calcium Channels, L-Type; D018076:DNA, Complementary; D009124:Muscle Proteins; D019837:Ryanodine Receptor Calcium Release Channel; D002118:Calcium