Turner syndrome in men and nunan syndrome

Turner's syndrome in men and Noonan's syndrome are rare and insufficiently studied diseases. Very often in the literature they are treated as synonyms. Most often, Turner's syndrome( in men and women) refers to a syndrome in which a set of sex chromosomes 45, XO or mosaicism is determined( in men 46, XY / 45, XO).The Noonan syndrome refers to the Turner phenotype( external manifestations) with a normal set of chromosomes. The latter can occur both with the female and with the male phenotype.

The basis for the development of Turner's syndrome in men, as in the case of the syndrome XX in men, is the transfer of part of the genetic material from the paternal Y chromosome to other chromosomes, which makes it possible to form a male appearance.

Noonan syndrome is transmitted by an autosomal dominant type of inheritance.

Both syndromes are characterized by short stature and underdevelopment of the gonads. The degree of underdevelopment of the latter is different: from total absence to a small underdevelopment of the testicles. There is an insufficient development of the body according to the male type: scanty hair on the pubic and face, insufficient development of the muscles, etc. In addition, in both cases there are somatic disorders characteristic of the Shereshevsky-Turner syndrome in women: a barrel chest, short neckwith pterygoid folds, deformation of the auricles, etc. Often various defects of internal organs and eyes are formed. Some people have mental retardation. The content of gonadotropic hormones in the pituitary gland in the blood serum is increased, testosterone( male sex hormone) is decreased. In the study of ejaculate, an inadequate number of spermatozoa in a unit of volume of various degrees is most often detected. When radiologic examination of the bone system, there is a moderate lag of the bone age from the passport age. In the syndrome of Noonan in 55-75% of cases, heart and large vascular defects are detected.

Treatment consists in carrying out substitution therapy with androgens( male sex hormones) in case of pronounced insufficiency.