Mental status of females with an FMR1 gene full mutation.

نویسندگان

  • B B de Vries
  • A M Wiegers
  • A P Smits
  • S Mohkamsing
  • H J Duivenvoorden
  • J P Fryns
  • L M Curfs
  • D J Halley
  • B A Oostra
  • A M van den Ouweland
  • M F Niermeijer
چکیده

The cloning of the FMR1 gene enables molecular diagnosis in patients and in carriers (male and female) of this X-linked mental retardation disorder. Unlike most X-linked disorders, a considerable proportion of the female carriers of a full mutation of the FMR1 gene is affected. In this study, the intelligence quotients (IQs) were ascertained by the Wechsler Adult Intelligence Scale in 33 adult females with a full mutation, with 28 first-degree adult female relatives (mainly sisters) without a full mutation as controls. Seventy-one percent of the females with a full mutation had IQ scores below 85. In paired analysis, no significant correlation could be detected between the IQs of the females with a full mutation and those of their first-degree female relatives, reflecting a dominant effect of the FMR1 gene full mutation in the mental development of females. Considering females with a full mutation only, we observed a significant relation between the proportion of normal FMR1 alleles on the active X chromosome and IQ. We present a model to explain this relationship.

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عنوان ژورنال:
  • American journal of human genetics

دوره 58 5  شماره 

صفحات  -

تاریخ انتشار 1996