Screening the dystrophin gene suggests a high rate of polymorphism in general but no exonic deletions in schizophrenics

The dystrophin gene, located at chromosome Xp21, was evaluated as a candidate gene in chronic schizophrenia in response to the report of a large family in which schizophrenia cosegregated with Becker muscular dystrophy [Zatz et al., 1991: Am J Hum Genet 49: A364; 1992: J Med Genet 30(2):131- 134]. Genomic DNA from 94 men with chronic schizophrenia was evaluated by Southern blot analysis using cDNA probes that span exons 1-59. No exonic deletions were identified. An unexpectedly high rate of polymorphism was calculated in this study and two novel polymorphisms were found, demonstrating the usefulness of the candidate gene approach even when results of the original study are negative.