Objectives: 45,X/46,X,idic(Y)(q10) mosaicism with variable phenotypes is considered to be a rare sex chromosomal disorder. Here, we report three cases of isodicentric Y chromosomes with mosaic karyotype: a boy with short stature and two infertile male patients with non-obstructive azospermia.
Method: G and C banding, FISH and Y microdeletion techniques were performed using peripheral blood lymphocytes of the patients according to standard procedures.
Results: All three patients were detected to be mosaic as 45,X/46,X,idic(Y)(q10) and lacked the AZFb and AZFc regions on the Y chromosome.
Conclusion: 46,X,idic(Y)(q10)/45,X mosaicism may manifest in a spectrum of phenotypes. This variable phenotype that is noted in these patients are both due to the presence of isodicentric Y chromosomes and to the proportion and tissue distribution of specific cell lines as well, most notably 45,X. Importantly, isodicentric Yq with losses in the long arm of the Y chromosome may lead to the deletion of critical AZF region. In summary, detection of structural abnormalities of Y chromosome and mosaic pattern will provide necessary information allowing a better genetic counseling.