OBJECTIVE: To report a novel clinical and genetic presentation of a patient with 
4H syndrome, which is a recently described leukodystrophy syndrome characterized 
by ataxia, hypomyelination, hypodontia, and hypogonadotropic hypogonadism.
DESIGN: Case report.
SETTING: University teaching hospital.
PATIENT: A 20-year-old male patient with 4H syndrome.
RESULTS: The patient was found to have delayed tooth eruption and a late-onset 
growth hormone deficiency without overt growth failure. He was a compound 
heterozygote for the novel missense mutations R1005H and A1331T of POLR3A, which 
codes for the largest subunit of RNA polymerase III.
CONCLUSION: This is the first report of this type of leukodystrophy from 
southeastern Europe, which suggests that POLR3A mutations should be suspected in 
patients with hypomyelination and various central nervous system–based endocrine 
abnormalities.