ABSTRACT
Turner syndrome is diagnosed by the combination of certain phenotypic characteristics with the absence of one of the X chromosome. This absence may be total or partial, as occurs in isochromosomes Xq. The phenotypic consequences of these depend on two factors: the characteristics of the lost genes and the percentage of cells 45, X in mosaicisms. The clinical features also change with the cytogenetic pattern. Short stature is the most common phenotypic manifestation, as it is due to the haploinsufficiency of the SHOX gene on the short arm of X chromosomes. Thus, when there is isochromosomes on the long arms, short stature is always present. However, the typical features of this syndrome could be absent, and the diagnosis can be delayed. This occurred in our patients, who will not be able to obtain optimum benefits with growth hormone treatment.
