title: Human chromosomal fragile site FRA16B is an amplified AT-rich minisatellite repeat.
abstract: Fragile sites are nonstaining gaps in chromosomes induced by specific tissue culture conditions. They vary both in population frequency and in the culture conditions required for induction. Folate-sensitive fragile sites are due to expansion of p(CCG)n trinucleotide repeats; however, the relationship between sequence composition and the chemistry of induction of fragile sites is unclear. To clarify this relationship, the distamycin A-sensitive fragile site FRA16B was isolated by positional cloning and found to be an expanded 33 bp AT-rich minisatellite repeat, p(ATATA TTATATATTATATCTAATAATATATC/ATA)n (consistent with DNA sequence binding preferences of chemicals that induce its cytogenetic expression). Therefore the mutation mechanism associated with trinucleotide repeats is also a property of minisatellite repeats (variable number tandem repeats).
authors.affiliation: Department of Cytogenetics and Molecular Genetics, Women's and Children's Hospital, North Adelaide, Australia. rrichard@medicine.adepaide.edu.au
authors.forename: S
authors.initials: S
authors.lastname: Yu
authors.forename: M
authors.initials: M
authors.lastname: Mangelsdorf
authors.forename: D
authors.initials: D
authors.lastname: Hewett
authors.forename: L
authors.initials: L
authors.lastname: Hobson
authors.forename: E
authors.initials: E
authors.lastname: Baker
authors.forename: H J
authors.initials: HJ
authors.lastname: Eyre
authors.forename: N
authors.initials: N
authors.lastname: Lapsys
authors.forename: D
authors.initials: D
authors.lastname: Le Paslier
authors.forename: N A
authors.initials: NA
authors.lastname: Doggett
authors.forename: G R
authors.initials: GR
authors.lastname: Sutherland
authors.forename: R I
authors.initials: RI
authors.lastname: Richards
mesh_terms: D001482:Base Composition; D001483:Base Sequence; D015139:Blotting, Southern; D043283:Chromosome Fragile Sites; D002873:Chromosome Fragility; D002885:Chromosomes, Human, Pair 16; D003001:Cloning, Molecular; D004276:DNA, Satellite / Q000737:chemistry; D005784:Gene Amplification; D006801:Humans; D018598:Minisatellite Repeats; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic
chemical_list: D004276:DNA, Satellite