THE JUBERG-MARSIDI SYNDROME MAPS TO THE PROXIMAL LONG ARM OF THE X-CHROMOSOME (XQ12-Q21)

Juberg-Marsidi syndrome (McKusick 309590) is a rare X-linked recessive condition characterized by severe mental retardation, growth failure, sensorineural deafness, and microgenitalism. Here we report on the ge netic mapping of the Juberg-Marsidi gene to the proximal long arm of t he X chromosome (Xq12-q21) by linkage to probe pRX214H1 at the DXS441 locus (Z = 3.24 at theta = .00). Multipoint linkage analysis placed th e juberg-Marsidi gene within the interval defined by the DXS159 and th e DXYS1X loci in the Xq12-q21 region. These data provide evidence for the genetic distinction between juberg-Marsidi syndrome and several ot her X-linked mental retardation syndromes that have hypogonadism and h ypogenitalism and that have been localized previously. Finally, the ma pping of the Juberg-Marsidi gene is of potential interest for reliable genetic counseling of at-risk women.