Mix Gonadal Dysgenesis Associated with Ring Y Chromosome Mosaics in a Phenotypic Male

Abstract

Ring chromosomes are present in 1 in 25,000 human fetuses; 99% arise de novo while less than 1% of rings are inherited. This chromosomal rearrangement may arise through a cytogenetic mechanism involving breaks in chromosome arms and fusion of the proximal broken ends, leading to a loss of distal material. Most patient Y ring chromosomes are present in a 45,X/46,X,r(Y) mosaic karyotype; molecular analyses of infertile men have shown that it is not rare to find r(Y) in these patients. However, the clinical spectrum in those cases with a 45,X cell line is broad and depends on the percentage of the monosomic cell line in different tissues. Y chromosome abnormalities and 45,X mosaic karyotypes are often associated with disorders of sex determination. Here, we report a male patient with hypospadias, cryptorchidism and a mosaic karyotype containing a low proportion of 45,X monosomic cells and multiple ring Y chromosomes in peripheral blood. Clinical, surgical, and molecular evidence was sufficient for a diagnosis of mixed gonadal dysgenesis. We suggest that a detailed cytogenetic and molecular analysis should be done in all males with bilateral descended testes and infertility.

Molecular Analysis of Ring Y Chromosome in a 10-Year-Old Boy with Mixed Gonadal Dysgenesis and Growth Hormone Deficiency

“…As with one patient reported previously [12], our patient was obese with significant acanthosis nigricans and pseudogynecomastia. His obesity was secondary to excessive food intake, consistent with the family’s overall nutrition.…”

“…According to the literature, the association of mixed gonadal dysgenesis and ring Y chromosome is extremely rare [2,12]. Our patient is the third patient with such abnormalities to be described in the literature.…”

“…There are few published reports in which ring the Y chromosome is directly associated with a MGD, but only exceptionally has the ring chromosome been analyzed by molecular techniques. These published MGD patients with a ring Y chromosome had short stature, but none of them had growth hormone (GH) deficiency [2,12]. Here, we present the molecular cytogenetic and molecular characterization of a ring Y chromosome mosaicism in a 10-year-old boy with MGD, short stature and GH deficiency.…”

A Rare Combination of Mosaic Ring Y Chromosome and Shox Gene Deletion in an Infertile Male

“…Ring kromozom oluşumunda majör mekanizma, kromozomun her iki kolunda ortaya çıkan ve genetik materyal kaybına neden olan terminal kırıklar sonucu oluşan yapışkan uçların füzyondur.Çoğunlukla de novo görülmekle birlikte, tüm ring kromozomların yalnızca %1 veya daha azı ebeveynlerden kalıtılarak ortaya çıkmaktadır. 4,5 Müşerref…”