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Updated: Jun 28, 2026

Exploring X Chromosomal Aberrations in Ovarian Cells by Using Fluorescence In Situ Hybridization
Published on: April 7, 2023
Genetic characterization of two 46,XX males without gonadal ambiguities
Agata Minor1, Fawziah Mohammed, Alla Farouk
1Department of Obstetrics and Gynaecology, University of British Columbia, Vancouver, BC, Canada.
Purpose:
To evaluate hypotheses which explain phenotypic variability in sex determining region Y positive 46,XX males. We investigate two 46,XX males without gonadal ambiguities.
Methods:
Cytogenetic and molecular analyses were used to identify the presence of Y chromosome material and to map the translocation breakpoint. Finally, the pattern of X chromosome inactivation was studied using the methylation assay at the androgen receptor locus.
Results:
The presence of Y chromosome material, including the sex determining region Y gene, was demonstrated in both men. However, the amount of translocated Y chromosome material differed between the patients. Different X chromosome inactivation patterns were found in the patients; random in one patient and non-random in the other.
Conclusions:
We found a lack of association between phenotype and X chromosome inactivation pattern. Our cytogenetic and molecular analyses show support for the position effect hypothesis explaining the phenotypic variability in XX males.
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