The gene shows similar pleiotropism as it is demonstrated for NARS2 in this study since in addition to DFNB89, compound heterozygous KARS mutations have been shown to cause Charcot Marie Tooth disease and developmental delay as well as severe infantile disease with microcephaly and white matter abnormalities, seizures and vision loss [12,15]. This evidence concerns the gene KARS1 and Charcot-Marie-Tooth disease.