title: Characterization of a human orphon 28 S ribosomal DNA.
abstract: We have isolated clones in which two regions of the human genome are represented, each containing an orphon: a dispersed copy of 28S rDNA. Nucleotide (nt) sequence analysis established that one of these, H28S-O1, corresponds to nt 3627-4105 of human 28S rDNA, but in a mutated form. The orphon was flanked on one side by a portion of the L1Hs long interspersed repeat family of the human genome. Although H25S-O1 is not flanked by the terminal direct repeats characteristic of transposed DNA, it is possible that it is a processed pseudogene.
mesh_terms: D001483:Base Sequence; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004275:DNA, Ribosomal / Q000235:genetics*; D006801:Humans; D005810:Multigene Family; D009154:Mutation; D012091:Repetitive Sequences, Nucleic Acid
chemical_list: D004275:DNA, Ribosomal