Cognition Associated with Dystrophin Deletion in Duchenne Muscular Dystrophy

ABSTRACT

OBJECTIVE: To find correlations between the deletion of dystrophin gene and cognitive status in Duchenne muscular dystrophy (DMD). METHOD: Cognitive abilities of 49 DMD children with dystrophin deletion were tested. Korean Wechsler Intelligence Scale for children was used to evaluate the cognitive status in DMD. Gene deletion was classified into two groups according to the location of the rearrangement (proximal region central and 3' region of the gene). RESULTS: Molecular study by multiplex PCR (Polymerase Chain Reaction) of dystrophin exons was performed to identify 49 deletions in the 110 DMD patients. 13 out of 49 DMD were mentally impaired. In patients with distal deletions, total IQ (Intelligence Quotient) score was lower than the those with proximal deletions; which was not statistically significant. And the difference of the verbal and performance intelligence scale was not statistically significant. But comparisons of molecular and neuropsychological features showed that deletions localized in the central and 3' regions of the gene were preferentially associated with the mental impairement. CONCLUSION: We concluded that deletions in the distal portions of the gene were more related to the mental retardation, although deletions with variable locations might lead to cognitive impairments.