Novel Mutation chrX:110644366 C>A of the DCX Gene in 4-year-old Girl with Sporadic Double Cortex Syndrome

Abstract

Subcortical band heterotopia (SBH), also known as double cortex syndrome (DC), is listed as a "rare disease" by the Genetic and Rare Diseases Information Center of the National Institutes of Health with an incidence of 1 to 200,000 people in the population. The cause of the disease is mutation in the DCX gene (also known as DBCN, XLIS) on chromosome Xq22.3-q23. SBH is an X-linked dominant disorder. Traditionally, genetic testing for SBH has been done in the order of the probability of detection of mutation according to the radiologic features, but the success rate could be variable with this time-consuming approach. In this study, novel mutation chrX: 110644366C>A in the DCX gene was identified in a 4-year-old Russian girl with sporadic SBH. The present report demonstrates that whole-exome sequencing may be a useful tool for the identification of previously known and de novo mutations in children with SBH as well as malformations of cortical development.

Keywords

• Double cortex syndrome
• absence seizures
• DCX gene
• de novo mutations