NCIt definition : An inherited, usually autosomal recessive condition cause by mutation(s) in the RNASEH2B
gene, encoding ribonuclease H2 subunit B. Clinical features and onset may vary significantly,
but is characterized in its most severe form by cerebral atrophy, leukodystrophy,
intracranial calcifications, chronic cerebrospinal fluid (CSF) lymphocytosis, and
increased concentrations of CSF alpha-interferon.;