Genética humana y embriología

Y-Chromosome Detection in Turner Syndrome

Abstract

Susana Fernandes, Vânia Ventura, Sofia Dória and Alberto Barros

Turner syndrome is a chromosomal disorder characterized by the presence of a single normal X chromosome in women. Additionally to the X chromosome monosomy, other cell lines can co-exist, containing the Y chromosome or part of it. The presence of Y chromosome in patients with Turner syndrome represents an increased risk (15- 30%) of developing gonadoblastoma. In this study we screened for the absence/presence of four genes mapped on Y chromosome (SRY, TSPY, DDX3Y and HSFY) in 98 female samples obtained from different tissues, namely peripheral blood, amniotic fluid, gonadal tissue and miscarriages samples, previously characterized cytogenetically having at least one cell line with monosomy X or an abnormal X chromosome. We also evaluate the importance of a molecular test for detection of Y chromosome sequences using a combination of conventional cytogenetic methods and DNA analysis. Three miscarriages and one gonadal tissue presented Y-chromosome DNA sequences out of the 98 studied samples. We have discussed the higher frequency of the Y sequences in spontaneous abortions with 45, X karyotype and we have advised the detection of Y-chromosome material in Turner patients in order to improve the clinical orientation and the consequent prognosis.