- A 17-bp insertion and a Phe215----Cys missense mutation in the dihydrolipoyl transacylase (E2) mRNA from a thiamine-responsive maple syrup urine disease patient WG-34. Fisher, C.W., Lau, K.S., Fisher, C.R., Wynn, R.M., Cox, R.P., Chuang, D.T. Biochem. Biophys. Res. Commun. (1991)