Aspartoacylase gene was cloned and localized on the short arm of chromosome 17 (9,22). The human aspartoacylase gene spans 30 kb, contains five introns and six exons coding for 313 aminoacids, an enzyme with a molecular weight of approximately 36 kDa.
There are two mutations, E285A and Y231X that account for over 98% of the mutations among Ashkenazi Jewish population (14,18,23-25). Carrier frequency for CD among Ashkenazi Jewish populations has ranged from 1/37 to 1/40 (26,27). This high frequency of carriers indicates that routine preventive measure using DNA analysis for the common Jewish mutations is recommended for Ashkenazi Jews. Currently, carrier detection for CD is included in a panel of several diseases with high frequency in the Ashkenazi Jewish population.
The most common mutation in non-Jewish patients is A305E (14). There have been over 40 mutations identified in various ethnic groups (14,17,18). Some mutations in exon 6 of the gene shows polymorphism that does not change the enzyme activity (28,29). Therefore expression studies are important to understand functional significance of mutations (30).
Was this article helpful?