MedGen

The two forms of deoxyguanosine kinase (DGUOK) deficiency are a neonatal multisystem disorder and an isolated hepatic disorder that presents later in infancy or childhood. The majority of affected individuals have the multisystem illness with hepatic disease (jaundice, cholestasis, hepatomegaly, and elevated transaminases) and neurologic manifestations (hypotonia, nystagmus, and psychomotor retardation) evident within weeks of birth. Those with isolated liver disease may also have renal involvement and some later develop mild hypotonia. Progressive hepatic disease is the most common cause of death in both forms. [from GeneReviews]

Noncirrhotic portal hypertension-1 (NCPH1) is an autosomal recessive disorder characterized by onset of portal hypertension associated with hepatosplenomegaly in the first or second decades of life, in the absence of cirrhosis, known extrahepatic diseases, or splanchnic venous thrombosis. Liver function is normal, and the disorder is relatively benign (Vilarinho et al., 2016). Genetic Heterogeneity of NCPH See also NCPH2 (619463), caused by mutation in the GIMAP5 gene (608086) on chromosome 7q36. [from OMIM]

Autosomal recessive progressive external ophthalmoplegia with mitochondrial DNA deletions-4 (PEOB4) is characterized by adult onset of eye muscle weakness and proximal limb muscle weakness associated with deletions of mtDNA on skeletal muscle biopsy, which results from defective mtDNA replication in post-mitotic muscle tissue. Additional features are more variable (summary by Ronchi et al., 2012). For a discussion of genetic heterogeneity of autosomal recessive PEO, see PEOB1 (258450). [from OMIM]