Los errores congénitos del metabolismo como enfermedades raras con un planteamiento global específico Inborn errors of metabolism as rare diseases with a specific global situation

So-called congenital metabolic diseases (CMD) are a consequence of biochemical alterations originating in the genes that result in the alteration of a protein. Depending on this protein’s function - whether as an enzyme, a hor mone, a receiver-transporter of a cellular membrane or forming part of a cellular organelle (lysosome, peroxysome) ‐ different groups of diseases emerge, which cause the most outstanding characteristic of inborn errors of metabolism (IEM): their clinical heterogeneity. The majority of these dis eases are autosomal recessive, with a limited number of asymptomatic carriers, but there are also those ruled by an autonomous, dominant character inheritance or linked to the X chromosome. Taken individually, CMDs are highly infrequent, but taken as a whole CMDs (of which over 500 have been described to date) can affect 1/500 of the new born. A common characteristic of many CMDs is the possi bility of dietary treatment and treatment with enzymatic replacement.