title: A fragile X male with a broad smear on Southern blot analysis representing 100-500 CGG repeats and no methylation at the EagI site of the FMR-1 gene.
abstract: Fragile X DNA studies were carried out on all obligate carriers of a large fragile X family with 10 mentally retarded individuals. One 64-year-old carrier man with an altered FMR-1 allele was not described as being mentally retarded or as having any limitations in function. He was married, raised 8 children, and worked as an auto mechanic. On examination, he had macrocephaly and mild macroorchidism but few of the other typical physical findings of males with fragile X syndrome. His Full Scale IQ is 73, and his Vineland Adaptive Behavior Composite is 73. On the Woodcock-Johnson Psycho-Educational Battery-Revised, he achieved standard scores of 64 in Reading, 55 in Math, and 83 in Knowledge. His DNA findings showed a broad smear on Southern blot analysis of 100-500 CGG repeats and no methylation at the EagI site upstream of the FMR-1 protein coding region. His FMR-1 protein production is 12% of normal. His daughters all have large premutations, with somatic instability in the size of the CGG repeat lengths. They all have evidence of academic underachievement and 2 have physical characteristics frequently described in individuals with fragile X.
authors.affiliation: Department of Pediatrics, Duke University Medical Center, Durham, North Carolina 27710, USA.
authors.forename: A M
authors.initials: AM
authors.lastname: Lachiewicz
authors.forename: G A
authors.initials: GA
authors.lastname: Spiridigliozzi
authors.forename: A
authors.initials: A
authors.lastname: McConkie-Rosell
authors.forename: D
authors.initials: D
authors.lastname: Burgess
authors.forename: Y
authors.initials: Y
authors.lastname: Feng
authors.forename: S T
authors.initials: ST
authors.lastname: Warren
authors.forename: J
authors.initials: J
authors.lastname: Tarleton
mesh_terms: D015139:Blotting, Southern; D004247:DNA / Q000097:blood; D019175:DNA Methylation; D015252:Deoxyribonucleases, Type II Site-Specific; D005260:Female; D005600:Fragile X Syndrome / Q000235:genetics* / Q000503:physiopathology / Q000523:psychology; D006580:Genetic Carrier Screening; D006801:Humans; D008607:Intellectual Disability / Q000235:genetics; D008297:Male; D008875:Middle Aged; D010375:Pedigree; D015183:Restriction Mapping; D018911:Trinucleotide Repeats
chemical_list: D004247:DNA; C046751:endodeoxyribonuclease XmaIII; D015252:Deoxyribonucleases, Type II Site-Specific