title: Fragile X syndrome: diagnosis using highly polymorphic microsatellite markers.
abstract: We describe two highly polymorphic microsatellite AC repeat sequences, VK23AC and VK14AC, which are closely linked to the fragile X at Xq27.3. Both VK23AC (DXS297) and VK14AC (DXS292) are proximal to the fragile site. Two-point linkage analysis in 31 fragile X families gave (a) a recombination frequency of 1% (range 0.00%-4%) with a maximum lod score of 32.04 for DXS297 and (b) a recombination frequency of 7% (range of 3%-15%) with a maximum lod score of 12.87 for DXS292. Both of these polymorphisms are applicable to diagnosis by linkage in families with fragile X syndrome. A multipoint linkage map of genetic markers at Xq27.3 was constructed from genotyping these polymorphisms in the CEPH pedigrees. The DXS292 marker is in the DXS98-DXS297 interval and in 3 cM proximal to DXS297.
authors.affiliation: Department of Cytogenetics and Molecular Genetics, Adelaide Children's Hospital, North Adelaide, South Australia.
authors.forename: R I
authors.initials: RI
authors.lastname: Richards
authors.forename: Y
authors.initials: Y
authors.lastname: Shen
authors.forename: K
authors.initials: K
authors.lastname: Holman
authors.forename: H
authors.initials: H
authors.lastname: Kozman
authors.forename: V J
authors.initials: VJ
authors.lastname: Hyland
authors.forename: J C
authors.initials: JC
authors.lastname: Mulley
authors.forename: G R
authors.initials: GR
authors.lastname: Sutherland
mesh_terms: D000483:Alleles; D001345:Autoradiography; D001483:Base Sequence; D004247:DNA / Q000235:genetics*; D004276:DNA, Satellite; D005600:Fragile X Syndrome / Q000235:genetics*; D008040:Genetic Linkage; D005819:Genetic Markers; D006801:Humans; D008126:Lod Score; D008969:Molecular Sequence Data; D010375:Pedigree; D011110:Polymorphism, Genetic; D012091:Repetitive Sequences, Nucleic Acid
chemical_list: D004276:DNA, Satellite; D005819:Genetic Markers; D004247:DNA