A simple fragile X PCR assay with 7-deazaguanine-substituted DNA visualized by ethidium bromide.
A deazaguanine-substituted DNA PCR product from FMR-1 (the fragile X mental retardation syndrome gene) can be efficiently visualized with ethidium bromide on standard agarose gels. Normal-sized alleles (less than 54 CGG repeats) generated strong, easily visible bands in the expected size range of 491-635 bp. Southern blot analysis and radioactive PCR on sequencing gels were used to verify that the 74 males (out of 245 total tested) whose DNA failed to generate a visible band contained premutations or full mutations. This technique can be used as an inexpensive screen for fragile X syndrome among developmentally delayed males.
Cao
J
J
Collaborative Diagnostics, Inc., Waltham, MA 02154.
Tarleton
J
J
Barberio
D
D
Davidow
L S
LS
D000483:Alleles; D001483:Base Sequence; D015139:Blotting, Southern; D004247:DNA / Q000032:analysis* / Q000235:genetics*; D004996:Ethidium; D005600:Fragile X Syndrome / Q000175:diagnosis / Q000235:genetics*; D006147:Guanine / Q000031:analogs & derivatives* / Q000032:analysis; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D009154:Mutation; D016133:Polymerase Chain Reaction / Q000379:methods*
D006147:Guanine; D004247:DNA; D004996:Ethidium; C066856:7-deazaguanine