Chromosome location: 22q13.33
Gene: TYMP
Protein affected: thymidine phosphorylase (TP)
Inheritance: autosomal recessive
Clinical features:
(1) leukoencephalopathy
(2) external ophthalmoplegia
(3) peripheral polyneuropathy
(4) cachexia
(5) enteric neuromyopathy with gastrointestinal dysmotility
Laboratory testing shows elevated plasma concentrations of thymidine and deoxyuridine.
Untreated the disease shows a progressive course with death during adulthood secondary to neuromuscular failure and/or malnutrition.
Therapeutic approaches may include:
(1) allogeneic hematopoietic stem cell transplant (AHSCT)
(2) infusion of erythrocyte encapsulated recombinant TP from E.coli (EE-TP), using the patient’s own red blood cells
