Charcot Marie Tooth disease type 4J with complex central nervous system features

We describe a family with Charcot Marie Tooth disease type 4J presenting with features of Charcot Marie Tooth disease plus parkinsonism and aphemia. Genetic testing found two variants in the FIG4 gene: c.122T>C (p.I41T) – the most common Charcot Marie Tooth disease type 4J variant – and c.1949‐10T>G (intronic). Proband fibroblasts showed absent FIG4 protein on western blot, and skipping of exon 18 by RT‐PCR. As most patients with Charcot Marie Tooth disease type 4J do not have central nervous system deficits, we postulate the intronic variant and I41T mutation together are causing loss of FIG4 protein and subsequently the central nervous system findings in our family.