Macroorchidism, Mental Retardation, and the Fragile X

Abstract
To the Editor: The fragile site at Xq27 or Xq28 is recognized as a new cytogenetic marker associated with one type of X-linked mental retardation, which probably accounts for a considerable proportion of mentally retarded males.Many questions about the fragile X, including its incidence in the general population and estimates of the frequency of mental retardation and possibly other clinical features, still need clarification.Large testes (macroorchidism) have been reported to be a frequent feature among mentally retarded males with the fragile X, but have not been found in all cases.1 2 3 To investigate whether clinical examination of the testes . . .