title: Fragile sites in chromosomes: possible model for the study of spontaneous chromosome breakage.
abstract: The tissue culture condition that is required for the type of chromosome breakage seen at most fragile sites, namely, the absence of folic acid and thymidine in the medium, greatly enhanced micronucleus formation in proliferating lymphocyte cultures from normal individuals. This suggests that chromosome breakage at fragile sites and the apparently spontaneous damage that gives rise to micronuclei are controlled by the same mechanism.
mesh_terms: D000293:Adolescent; D000328:Adult; D002467:Cell Nucleus / Q000187:drug effects / Q000648:ultrastructure; D002478:Cells, Cultured; D002648:Child; D002869:Chromosome Aberrations; D043283:Chromosome Fragile Sites; D002873:Chromosome Fragility; D003470:Culture Media; D004305:Dose-Response Relationship, Drug; D005260:Female; D005492:Folic Acid / Q000494:pharmacology; D006801:Humans; D008214:Lymphocytes / Q000648:ultrastructure; D008297:Male; D008875:Middle Aged; D013936:Thymidine / Q000494:pharmacology
chemical_list: D003470:Culture Media; D005492:Folic Acid; D013936:Thymidine