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.

Journal Article (Journal Article)

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.

Full Text

Duke Authors

Cited Authors

  • Lachiewicz, AM; Spiridigliozzi, GA; McConkie-Rosell, A; Burgess, D; Feng, Y; Warren, ST; Tarleton, J

Published Date

  • August 9, 1996

Published In

Volume / Issue

  • 64 / 2

Start / End Page

  • 278 - 282

PubMed ID

  • 8844065

International Standard Serial Number (ISSN)

  • 0148-7299

Digital Object Identifier (DOI)

  • 10.1002/(SICI)1096-8628(19960809)64:2<278::AID-AJMG9>3.0.CO;2-Q


  • eng

Conference Location

  • United States