[Human creatine kinase deficiency].
We describe a 56-year-old woman hospitalized under a diagnosis of acute myocardial infarction without an increase in serum creatine kinase(CK) activity during the clinical course. The patient had had no previous muscular symptoms. CK-M protein in the myocardial tissue of the patient was substantially lower(103 +/- 7 ng/mg protein) than that in control myocardial tissue(35,800 +/- 2860 ng/mg protein). Immunoreactive CK-M in the patient tissue sample was 0.3% of the value for the control sample. CK-M mRNA was 53-fold less in the patient sample compared with the control. This very low expression of CK-M mRNA was considered to be the primary reason for CK-M deficiency. Direct sequencing demonstrated a point mutation at residue 54 in exon2, which was specific for the patient. There were no other abnormalities found in the CK-M gene of the patient. This report identifies a molecular abnormality in human CK deficiency and discusses the physiologic relevance of CK-M.
Yamamichi
Hiroshi
H
Clinical Laboratory Medicine, West Kobe Medical Center, Kobe 651-2273.
Ohkawa
Jiro
J
D003402:Creatine Kinase / Q000172:deficiency* / Q000235:genetics; D052279:Creatine Kinase, MB Form; D005260:Female; D006801:Humans; D007527:Isoenzymes / Q000172:deficiency* / Q000235:genetics; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis / Q000235:genetics; D009206:Myocardium / Q000201:enzymology*; D017354:Point Mutation
D007527:Isoenzymes; D003402:Creatine Kinase; D052279:Creatine Kinase, MB Form