Report of Two Turner affected patients with dicentric X chromosome

Turner's syndrome is one of the relatively common chromosomal disorders characterized by the absence of all or part of one sex chromosome, with a prevalence of near one in 2500 live birth females. Most typical clinical characteristics of this syndrome include primary amenorrhea, hypogonadism, short stature, digital anomalies, and low hair line at the back of the neck. A large number of affected individuals have a 45,X monosomy; nevertheless, other structural abnormalities of X chromosome or 45,X with cell line mosaicism can also fulfill the criteria. In the current study we report two turner affected patients with dicentric X making an attempt to explain their phenotypes associated with deleted areas.

The first case was a 13-year old female who had edema and lymphoma during infancy. As she grew up, other symptoms of Turner’s syndrome such as short stature, broad shoulders, widely spaced nipples, short metacarpals, small womb, premature ovarian, and higher levels of FSH, LH, and prolactin were apparent. The second patient was a 12 year-old girl without obvious Turner’s syndrome in her infancy, but during her puberty, she showed short stature, short neck, broad chest, normal womb, premature ovarian, normal LH, and increased levels of FSH and prolactin.

The results of G-banding karyotyping depicted that the first patient had 46,X,dic(X) and she was monosomy for short arm of X chromosome, while the second patient was mosaic 45,X(60%)/46,X,dicX(40%). Considering the areas which have been deleted and also heterogenic phenotypes of each patient, roles of every involved gene in that regains have been regarded. With this regard for the exact detection of deleted areas, fluorescence in situ hybridization (FISH) is recommended. Also, carrier detection of parents with a history of affected child for assessing chromosomal abnormalities with the aim of preventing further affected child during their conception is suggested.