title: In vitro reversal of fragile-X expression by exogenous thymidine.
abstract: A virtually thymidine free medium was used to test the effects of exogenous thymidine on lymphocyte expression of the fragile-X. De novo pathway thymidylic acid synthesis in the cells was blocked by FUdR. Our results suggest that in vitro exogenous thymidine is directly responsible for suppressing expression of the fragile-X. More importantly, delayed addition of exogenous thymidine can negate fragile-X expression after it has first been induced by FUdR.
mesh_terms: D003470:Culture Media; D005467:Floxuridine / Q000494:pharmacology; D005600:Fragile X Syndrome / Q000209:etiology / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D008214:Lymphocytes / Q000187:drug effects*; D008297:Male; D012729:Sex Chromosome Aberrations / Q000378:metabolism*; D013936:Thymidine / Q000494:pharmacology*; D013938:Thymidine Monophosphate / Q000096:biosynthesis
chemical_list: D003470:Culture Media; D005467:Floxuridine; D013938:Thymidine Monophosphate; D013936:Thymidine