A novel mutation in a family with non-erythroid variant form of acute intermittent porphyria

Acute intermittent nt porphyria (AIP), an autosomal dominant disorder, is d ivided into two forms, the classical form (mort than 95%) and the non-eryth roid variant form, according to erythroid porphobilinogen deaminase (PBGD) activity. In the variant form, the PBGD activity is essentially normal. Det ection of presymptomatic mutation carriers relies on a DNA test. This varia nt form of AIP is very rare, with only nine families carrying five differen t mutations reported ill the literature, Here we report a novel G-to-T tran sversion in the first position of intron 1 of the PBGD gene in a family wit h this variant form of AIP. We also review all previously reported cases an d propose an effective diagnostic approach.