Coincidence of two genetic forms of Charcot–Marie–Tooth disease in a single family

The authors report a family in which two affected first cousins had a severe demyelinating Charcot–Marie–Tooth disease (CMT) phenotype. One had related parents, and there were no other affected relatives, suggesting an autosomal recessive mode of inheritance. Molecular studies showed that a de novo duplication in 17p11.2 and a second mutation in MTMR2 were present.