A Novel Mutation in the ROGDI Gene in a Patient with Kohlschütter-Tönz Syndrome.

Kohlschütter-Tönz Syndrome (KTZS) is an autosomal recessive disorder caused by mutations in the ROGDI gene. This syndrome is characterized by epilepsy, psychomotor regression and amelogenesis imperfecta. In this paper, we report a case of a 13-year-old Malian girl presenting with this rare disease. By genetic analysis, we identified a novel ROGDI homozygous mutation NM_024589.1: c.117+1G>T [Chr16 (GRCh37): g.4852382C>A] which confirmed the diagnosis of Kohlschütter-Tönz syndrome. The mutation abolishes the usual splice donor site of intron 2 which leads to the deletion of exon 2 and in-frame assembly of exon 3. Exon 2 encodes a highly conserved leucine-rich region that is essential for ROGDI protein function. Hence, this deletion may affect the function of the ROGDI protein.