Familial hypotonia of childhood caused by isolated 3-methylcrotonyl-coenzyme A carboxylase deficiency.
Hypotonia was the initial symptom in four siblings from a nonconsanguineous Tunisian-Jewish family. Plasma carnitine was severely deficient, and urinary organic acid analysis revealed increased excretion of 3-hydroxyisovaleric acid and 3-methylcrotonylglycine. 3-Methylcrotonyl-coenzyme A carboxylase activity was reduced in skin fibroblasts; pyruvate carboxylase and serum biotinidase activities were normal. We conclude that 3-methylcrotonyl-coenzyme A carboxylase deficiency should be added to the list of metabolic causes of familial hypotonia of childhood.
Elpeleg
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ON
Metabolic Unit, Shaare-Zedek Medical Center, Jerusalem, Israel.
Havkin
S
S
Barash
V
V
Jakobs
C
C
Glick
B
B
Shalev
R S
RS
D019735:Carbon-Carbon Ligases; D002331:Carnitine / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008025:Ligases / Q000172:deficiency* / Q000378:metabolism; D008297:Male; D009123:Muscle Hypotonia / Q000188:drug therapy / Q000201:enzymology / Q000235:genetics*; D011766:Pyruvate Carboxylase / Q000378:metabolism
D008025:Ligases; D019735:Carbon-Carbon Ligases; D011766:Pyruvate Carboxylase; C021573:methylcrotonoyl-CoA carboxylase; D002331:Carnitine