Robertsonian translocation associated with azoospermia

Repercusión clínica de las anomalías cromosómicas

The incidence of chromosome anomalies in newborn infants is 0.7-0.8 %. The phenotypic manifestations of chromosomal abnormalities are highly diverse. These anomalies may be present in phenotypically normal individuals in whom they can increase the risk of recurrent miscarriage and birth defects and/or mental retardation. It is important to determine this risk to provide patients with appropriate genetic counseling.

Pericentric inversion of chromosome 9 in infertile men

Reproductive condition was studied in 6 infertile men with pericentric inversion of chromosome 9. Semen analyses revealed one azoospermia, one oligozoospermia, three asthenozoospermias and one normozoospermia. Four cases showed normal levels of plasma gonadotropins and testosterone. The response of plasma testosterone to human chorionic gonadotropin was within the normal range in all cases. However, the administration of LH-RH resulted in abnormal response of plasma gonadotropin in all patients. These results indicate that infertile males with pericentric inversion of chromosome 9 have an abnormality in the hypothalamic-pituitary-testicular axis.

Structural variants of chromosome 9: a possible association with hypogonadotropic hypogonadism

We report two cases of structural variations of chromosome 9 associated with hypogonadotropic hypogonadism and azoospermia in adolescent boys. One patient also had a partially imperforated urethral meatus. Histological examination revealed that both had hypotrophic and underdeveloped testes. There was no LH and FSH response to LH-RH stimulation nor was there any response to naloxone tests. Basal and HCG stimulated plasma testosterone values were below normal prepubertal levels. As the administration of gonadotrophins did not improve the clinical and hormonal findings, alternative androgen therapy was necessary to achieve secondary sexual characteristics. Although they reached a good level of androgenization, their testes were still very small and azoospermia remained, as confirmed by repeated semen analyses. A possible association between chromosome 9 polymorphisms and hypothalamo-pituitary axis abnormalities is suggested. It is hypothesized that structural variants of chromosome 9 are not unrelated occurrences. Furthermore, and in view of the fact that they can lead to a high risk of azoospermia and infertility, such variants call for clinical investigation.

Hormone profiles and contralateral testicular histology in Down's syndrome with unilateral testicular tumor

Hormonal profiles and testicular histology were studied in two patients with Down's syndrome with unilateral testicular tumor. Plasma levels of LH and FSH were elevated above normal ranges in both cases. In case 1, plasma testosterone level was abnormally low, but prolactin level in plasma was within the normal range. Case 2 showed elevated concentration of plasma prolactin and normal level of plasma testosterone. The administration of LH-RH resulted in low response of plasma gonadotropins. The response of plasma testosterone to the administration of HCG was abnormally suppressed in both cases. Testicular histology showed reduction of Johnsen score count and tubular diameter, and an increase in wall thickness. These results indicated that male patients with Down's syndrome have an abnormality in hypothalamo-pituitary-gonadal axis.

Y-autosome translocation associated with azoospermia

Y-autosome translocation is a rare condition. We report here a case of balanced Y-autosome translocation associated with azoospermia. Nineteen cases of a balanced Y-autosome translocation associated with azoospermia are reviewed, and hormone condition and testicular histology are discussed.