title: Fragile sites in human chromosomes I. The effect of methionine on the Xq fragile site.
abstract: The Xq fragile site found in males having non-specific X-linked mental retardation was studied by varying the chemical and physical parameters of leukocyte cultures. Methionine was shown to be required for marker expression in both medium 199 and MEM. Banding studies indicated that methionine does not function as a stabilizing factor for the fragile site on Xq.
mesh_terms: D002478:Cells, Cultured; D002871:Chromosome Banding; D043283:Chromosome Fragile Sites; D002873:Chromosome Fragility; D003470:Culture Media; D005260:Female; D005819:Genetic Markers; D006801:Humans; D008607:Intellectual Disability / Q000235:genetics; D008297:Male; D008715:Methionine / Q000494:pharmacology*; D012730:Sex Chromosomes / Q000187:drug effects*; D014960:X Chromosome / Q000187:drug effects*
chemical_list: D003470:Culture Media; D005819:Genetic Markers; D008715:Methionine