Objective: To analyze unusual translocations involving a chromosome 1 whole arm and an acrocentric G chromosome p arm found in two men with azoospermia.
Design: Case report with review of the scientific literature.
Setting: Cytogenetics department.
Patient(s): Two men with azoospermia and normal hormonal levels.
Interventions(s): Peripheral blood lymphocytes were obtained for karyotype, and metaphases were studied by standard GBG, RBG, and CBG banding procedures.
Main outcome measure(s): Karyotype GBG, RBG, and CBG banding.
Result(s): Karyotype revealed balanced translocation involving a chromosome 1 whole arm and an acrocentric G chromosome p arm: 46,XY,t(1;21)(q11;p13) (patient 1) and 46,XY,t(1;22)(q11;p11) (patient 2).
Conclusion(s): With regard to published cases of whole-arm translocation of human chromosome 1 with an acrocentric p arm and a maternal origin of these abnormalities, we argue for an impairment of meiosis resulting in a high probability of quadrivalent-XY-body interaction. Male factor infertility might be due to two poor prognostic factors, first the involvement of human chromosome 1 (and its heterochromatic region) and second the involvement of an acrocentric chromosome p-arm breakpoint. This probable interaction between the pachytene quadrivalent and XY body might explain azoospermia.