Pyruvate dehydrogenase E1α deficiency in a family: Different clinical presentation in two siblings

pyruvate dehydrogenase (PDH) complex (PDHc) is responsible for the irrevers-The ible conversion of pyruvate to acetyl-CoA. PDHc is a multienzyme complex consisting of three catalytic subunits, pyruvate decarboxylase (E1), dihydrolipoamide acetyltransferase (E2), dihydrolipoamide dehydrogenase (E3), and two regulatory subunits, E1 kinase and phospho-E1 phosphatase. An abnormal E1a subunit, whose gene is located on the X chromosome, is the most frequent cause of PDH deciency. The clinical presentation of a PDH-E1a deciency (McKusick 312170) is variable.