Abnormality of a thiamine-requiring enzyme in patients with Wernicke-Korsakoff syndrome.

We studied a thiamine-requiring enzyme in cultured cells from four patients with the Wernicke-Korsakoff syndrome to determine whether these patients have a genetic predilection to thiamine deficiency. Transketolase in fibroblasts from the patients with the syndrome bound thiamine pyrophosphate less avidly than control lines. The apparent Km for thiamine pyrophosphate was 195 +/- 31 micron for transketolase in extracts of the patients' cells as compared to 16 +/- 2 micron in six control lines (means +/- S.E.M.: P less than 0.001). The ranges were 146 to 281 micron for the patients and 12 to 20 micron for the controls. The abnormality in transketolase persisted through serial passages in tissue culture in cells grown in medium containing excess thiamine and no ethanol, indicating that the aberrations were genetic rather than dietary. The abnormality of transketolase in this syndrome would presumably be clinically unimportant if the diet was adequate. These patients appear to have deleterious inborn enzymatic abnormalities of a type originally postulated by Garrod.