Teaching NeuroImages: Hypomyelinating leukodystrophy with hypodontia due to POLR3B

摘要

An 18-year-old German woman presented with progressive cerebellar ataxia since early childhood, delayed cognitive development, and hypogonadotropic hypogonadism. MRI demonstrated diffuse cerebral hypomyelination, cerebellar atrophy, and thin corpus callosum; X-ray revealed persistent milk teeth and hypoplastic crowns and roots (figure), indicative of 4H syndrome (hypomyelination, hypodontia, hypogonadotropic hypogonadism). POLR3B sequencing¹ revealed 2 compound heterozygous mutations (C527R [C.1579T>C] and the common ancestral V523E [C.1568T>A]²).