Table 2.

Criteria inborn errors of metabolism by Ferreira et al. (8).

Disruption of a metabolic pathway is considered necessary and sufficient for inclusion Regardless of laboratory abnormalities in standard biochemical tests Regardless of association with clinical manifestations of disease (unless defect is universal to all humans) Severity alone is not considered sufficient for separation into different entries when a single gene product is involved A different pathomechanism is considered necessary for separation into different entries when a single gene product is involved, regardless of the mode of inheritance The involvement of different gene products is considered sufficient for separation into different entries, even if the phenotype is similar The error must have been reported in more than a single family, and the involvement of the gene product must haven well characterized on an enzymatic or molecular level