Abnormalities of bile acids in serum and bile from patients with myotonic muscular dystrophy.

1. Serum bile acids in seven patients with adult type myotonic dystrophy and 22 normal persons were quantitatively analysed by gas-liquid chromatography and gas chromatography-mass spectrometry for cholesterol, gamma-glutamyltransferase and bilirubin. There was no bile obstruction in any patient. 2. Dexoycholic acid values in all mothers of patients with congenital type myotonic dystrophy were three times (2.1 mumol/l) that of the control (0.7 mumol/l). 3. Uncommon bile acids were detected in the patients' sera. One of them appeared to be dihydroxymono-oxocholanic acid, having a longer side chain. Another one appeared to be dihydroxycholanic acid, with a steroid-nucleus structure similar to chenodeoxycholic acid and with a longer side chain. 4. Biliary bile acids from three patients and one normal person were also analysed, and this revealed a remarkable decrease in ursodeoxycholic acid in the patients. 5. The presence of bile acid abnormality in patients with myotonic muscular dystrophy is proposed.