P0182 THE DEVELOPMENT OF APPROPRIATE STRATEGIES AND METHODS FOR MUTATION ANALYSIS IN THE ATP7B GENE

Abstract

Introduction: Wilson disease (WD) is an autosomal recessive disorder of copper metabolism resulting in accumulation of copper in various tissues. Herein we report the results of mutation analysis in a group of 127 WD families of various origins. Methods: Patients originating from Sardinia were first analyzed for the six most common mutations in this population using the multiplex PCR and Reverse dot blot analysis. Using the SSCP method, patients originating in Yugoslavia were first analyzed for 4 exons where the large majority of mutations identified in this population reside. Sardinian and Serbian DNA samples not completely characterized with the first step of analysis and the rest of DNA samples were analyzed for 10 exons, where most of mutations reside on the basis of previous studies and subsequently for the remaining exons of the ATP7B gene by SSCP analysis. Results: Using these approaches we characterized 87.4 % of the analyzed chromosomes and detected 64 WD causing mutations. The search of the six most common mutations in Sardinians and the study of exons 14,8,5,13 in Serbians led to the characterization of 80.4% and 76% of the analysed chromosomes respectively. SSCP analysis of 10 exons in the remaining ethnically mixed samples led us to characterize the 72.4% of the analysed chromosomes. In the Italian cohort there is some evidence of regional specific distribution of mutations. Conclusion: We conclude that mutation analysis stategy is possible in homogeneous populations by analysing the common mutations whereas in areas of genetic heterogeneity or in ethnically mixed populations a combination of the study of exon hot spots and of population or region specific mutations is necessary.