A novelTUBB4Amutation suggests that genotype-phenotype correlation of H-ABC syndrome needs to be revisited: Figure 1

Sir,We read with great interest the article on the rare childhood syndrome associated with TUBB4A and termed hypomyelination with atrophy of the basal ganglia and cerebellum (H-ABC) (Hamilton et al. , 2014 a ), the commentary by Carvalho and colleagues (2014), and the subsequent reply by Hamilton et al. (2014 b ).In their seminal paper on 42 unrelated H-ABC patients, Hamilton et al. (2014 a ) suggested the presence of genotype-phenotype correlation, arguing that a more benign phenotype is usually observed in patients with the common c.745G>A than in patients carrying other types of mutations. Carvalho et al. (2014) then reported two further patients, one carrying the c.745G>A mutation and the other carrying the novel c.1181T>G mutation, reinforcing the notion that there might exist a genotype-phenotype correlation of H-ABC syndrome. We wished to enter this debate giving examples of our experience, as we feel that sharing information and opinions will further enhance our understanding …