Fatal genetic defect causing Wolman disease.

Tested mothers carrying the OCT mutations were asymptomatic or a†ected to a much milder degree than their a†ected daughters. They revealed normal or only slightly increased orotic aciduria in the allopurinol loading test, supporting the probability of undeÐned or false negative results in carrier detection by this method. DNA analysis of the OCT gene showed it to be the most reliable diagnosis of female carrier status.