ACUTE INTERMITTENT PORPHYRIA - PREVALENCE OF MUTATIONS IN THE PORPHOBILINOGEN DEAMINASE GENE IN BLOOD-DONORS IN FRANCE

Objectives. Acute intermittent porphyria (AIP) is an autosomal dominan t disorder resulting from a 50% deficiency in porphobilinogen deaminas e (PBG deaminase). The true prevalence in the general population of mu tations in the PEG deaminase gene capable of causing ALP is unknown. H owever, it is important to identify asymptomatic carriers of AIP mutat ions because all are at: risk to have an acute attack. Design. We meas ured erythrocyte PEG deaminase from 3350 healthy blood donors. When a clear cut deficiency (< mean minus 2.5 SD) was found, the PEG deaminas e gene was analysed by molecular biology technics. Subjects. Four subj ects with PEG deaminase deficiency were identified. Two had mutations in the PEG deaminase gene which are known to cause AIP. Conclusion. We conclude that, in France, the mutations of the PEG deaminase gene sho w a high prevalence in the healthy population If only these two confir med latent cases are used for the calculation, in France the minimal p revalence of the AIP gene is 1:1675.