Related Experiment Video
Updated: Aug 14, 2026
A Seminiferous Tubule Squash Technique for the Cytological Analysis of Spermatogenesis Using the Mouse Model
Published on: February 6, 2018
Mosaic ring Y chromosome in two normal healthy men with azoospermia
Veronica Bertini1, Domenico Canale, Maria Patrizia Bicocchi
1Laboratory of Cytogenetics and Molecular Genetics, Azienda Ospedaliera Universitaria Pisana, Pisa, Italy.
Objective:
To better define by molecular and cytogenetic techniques ring Y chromosomes detected in 2 infertile men.
Design:
Case report.
Setting:
Molecular genetics/cytogenetics unit in a university hospital.
Patient(S):
Two infertile men with azoospermia, presenting a normal male phenotype with complete masculinization.
Intervention(S):
Karyotype and genetic counseling.
Main Outcome Measure(S):
Metaphases were studied by standard G- and Q-banding; fluorescent in situ hybridization and PCR were performed to analyze specific Y chromosome regions.
Result(S):
Chromosomal analysis detected a mosaicism with a Y chromosome ring cell line in 92% (patient 1) and 95% (patient 2) of the metaphases, coexisting with a 45,X cell line in the remaining metaphases. In patient 1, PCR analysis showed the presence of AZFa region and a partial deletion of AZFb region; AZFc region was deleted. In patient 2 all three AZF regions were deleted.
Conclusion(S):
A 45,X/46,X,r(Y) mosaicism can be detected not only in patients with Ullrich-Turner syndrome and in patients with various degrees of genital ambiguity but also in men presenting a normal phenotype. Their azoospermia can be explained by partial or total deletion of AZF regions.
Related Concept Videos
02:19The Y Chromosome Determines Maleness
Evolution
Around 300 million years ago, the two sex chromosomes diverged from two identical autosomal chromosomes. Over time, the Y chromosome has lost most of its genes, shrinking in size. Today,...
01:23Infertility in Males
01:43Sex-linked Disorders
01:29Nondisjunction
01:21Nondisjunction
02:02Meiosis II
The timing and cell division patterns of meiosis differ between males and females. In male meiosis, the centrosomes are part of the formation of the meiotic spindle. However, in oocytes, including that of humans, Drosophila,...