Deletion of Y chromosome involving the DAZ (deleted in azoospermia) gene in XX males

Neoplasms and pathology of sexual developmental disorders (intersex)

Continuing new insights into the biology of sexual development and advances in chromosome analysis have led to early identification and prompt treatment of the intersexual patient, the results of which facilitate a more normal life for affected individuals. Based on these advances, a classification of abnormal sexual development has been developed and refined that correlates the gonadal and genital anatomy with the chromosomal findings and specific genetic or metabolic defects. In a shift from a classification anchored on whether the intersex revolves about a specific gene or whole chromosomal abnormality, the current classification is organised by broader categories into which the intersexual disorders are divided into 'abnormalities of genital differentiation', due largely to the abnormal production or sensitivity of a single hormone, or 'abnormalities in sex determination', due to abnormal gonadal differentiation, usually testicular, with or without chromosomal aberration. The current classification is an integrated approach to this complex group of disorders and is organised according to the manner by which patients present as well as on the pathophysiological basis of the defect. The classification also groups patients who are at high risk for development of gonadal neoplasia.

A comparative genomic hybridization study in a 46,XX male

OBJECTIVE

To identify Y chromosome material in an azoospermic male with an XX karyotype.

DESIGN

Case report.

SETTING

Faculty of medicine and Centro de Patologia Celular (CPC) medical center.

PATIENT(S)

A 33-year-old man with infertility.

INTERVENTION(S)

G-banding, fluorescence in situ hybridization (FISH), polymerase chain reaction (PCR), and comparative genomic hybridization (CGH).

MAIN OUTCOME MEASURE(S)

FISH for X and Y chromosomes, PCR for the SRYgene and amelogenin gene in the Xp (AMGX) and (AMGY), and losses or gains with CGH.

RESULT(S)

FISH analysis using X and Y chromosome-specific probes showed an X chromosome containing Y chromosome sequences on the top of the short arm; this Y chromosome region was not visible by conventional cytogenetic analysis. PCR amplification of DNA showed the presence of the sex-determining region of the Y chromosome (SRY) and the amelogenin gene in the pseudoautosomal boundary of the X chromosome (AMGX). CGH confirmed the presence of the chromosome region Yp11.2-pter and detected the presence of the two otherwise normal X chromosomes.

CONCLUSION(S)

The two Xpter (XPAR1) pseudoautosomal regions present in this XX male suggest the need to reevaluate XX males using CGH and PCR to characterize the clinical variability in XX males due to genes other than those located on the Y chromosome.