45, x/46, x, r (x) karyotype in patients with clinical diagnosis of turner’s syndrome

Abstract

One out of 400 to 500 living newborns show sex chromosome abnormalities. Usually, the clinic characteristics due to alteration of those chromosomes are less severe than those produced by autosomic imbalance. This tolerance of the developing fetus to the excess or deficit in the X chromosome material, may be due, at least in part, to the presence of compensatory mechanisms related with the inactivation or not of the genetic material. Turner’s syndrome is characterized by short staFture, primary amenorrea, streak gonads and poor development of secondary sexual characteristics. At birth lymphedema of the dorsal surface of the hands and feet is common, but usually it disappears during lactation. Mental retardation is not a finding of this syndrome, however space-form perceptional deficits are described. All these manifestations of the syndrome have a close relation with the cytogenetic findings. The purpose of this paper is to describe the clinical manifestations and an uncommon X ring chromosome mosaicism in patients with Turner syndrome-like characteristics tended in the Medical Genetics Unit of the Medical School – Antioquia University. Clinical and cytogenetics aspects in these patients are discussed.