4H Leukodsytophy is a rare and devastating disease of the central nervous system. The name 4H stands for hypomyelination, hypogonadotropic hypogonadism and hypodontia. The disease is also known as POLR3-Related Leukodystrophy or 4H Syndrome.
Hypomyelination means that there is lack of myelin in the central nervous system, which results in problems in transmission of messages from the brain throughout the body. Hypogonadotropic hypogonadism means delayed or abnormal puberty because the central nervous system is not able to initiate it properly. Hypodontia means that not all teeth are present or there is abnormal development of teeth.
Symptoms tend to get progressively worse over time, and people with 4H Leukodystrophy suffer from motor problems, resulting in ataxia and loss of the ability to walk. They often develop difficulties swallowing, which leads to difficulties with eating and breathing. There is not yet a known cure.