title: The nucleotide sequence of a new human repetitive DNA consists of eight tandem repeats of 66 base pairs.
abstract: Three cloned human DNA fragments obtained from a fibroblast genomic DNA were sequenced and identified as containing members of the well-known 300-bp Alu family of interspersed, middle-repetitive DNA sequences. One of these cloned DNA fragments, p16, also contains members of a new repetitive DNA family, which repeats several thousand times in the human genome. Each member of the new 528-bp family consists of eight tandem repeats of a 66-bp sequence. An AluI recognition site is present at the same location in each repeat, and a 25-bp sequence occurs twice (as a tandem repeat) in each of the eight repeats. There is no sequence homology between the new 528-bp family and the 300-bp Alu family, and the new family lacks the flanking 7- to 20-bp direct repeats as well as the dAMP-rich sequences characteristic of the 300-bp Alu family. Construction of a putative evolutionary tree indicates that six duplication events are needed to give rise to the eight tandemly repeated 66-bp units in the new 528-bp family.
mesh_terms: D001483:Base Sequence; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004247:DNA; D006801:Humans; D007370:Interferon Type I / Q000096:biosynthesis; D009693:Nucleic Acid Hybridization; D012333:RNA, Messenger; D012091:Repetitive Sequences, Nucleic Acid
chemical_list: D007370:Interferon Type I; D012333:RNA, Messenger; D004247:DNA