inborn error of metabolism

Inborn errors of metabolism comprise a large class of genetic diseases involving disorders of metabolism. The majority are due to defects of single genes that code for enzymes that facilitate conversion of various substances (substrates) into others (products). In most of the disorders, problems arise due to accumulation of substances which are toxic or interfere with normal function, or to the effects of reduced ability to synthesize essential compounds. Inborn errors of metabolism are now often referred to as congenital metabolic diseases or inherited metabolic diseases, and these terms are considered synonymous.
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Inborn error of metabolism n. Any of a group of congenital disorders caused by an inherited defect in a single specific enzyme that results in a [more]Inborn error of metabolism - Community and Resources

Noun
1. any of a number of diseases in which an inherited defect (usually a missing or inadequate enzyme) results in an abnormality of metabolism
(hypernym) metabolic disorder
(hyponym) galactosemia