Reproductive hormone studies in three subjects with a Robertsonian translocation.

The reproductive hormone function was investigated in three subjects, two brothers and one unrelated patient, with a Robertsonian translocation, who had come to us because of infertility. Basal levels of LH, FSH, testosterone, 17-beta-estradiol and prolactin were repeatedly measured by radioimmunoassays. In addition, clomiphene citrate, synthetic LH-RH, hCG and TRH tests were carried out. Karyotypes complemented by G-banding and C-banding, repeated semen analyses, and testicular biopsies were also obtained. The karyotype of all three subjects was 45, XY-13, -14, +t(13; 14) (p11; q11). Semen analyses showed oligozoospermia, and reduced or reduced/normal sperm motility. In addition, a high percentage of atypical forms was present in all three subjects. Reproductive hormone measurements in our three patients were substantially normal. Only one of the two brothers exhibited slightly low LH and testosterone levels. Both brothers also had elevated estradiol levels. Gonadotropin and testosterone responses to respective provocative stimuli, as well as prolactin elevation following TRH, were normal. In conclusion, the semen abnormalities observed in these three subjects with Robertsonian translocation appear to be responsible for their impaired fertility. However, the reason why some carriers of the same translocation are fertile and some others are subfertile or infertile remains unclear. It might be speculated that an individual genetic variability is responsible for different degrees of spermatogenic failure, accompanied, in more severe cases, also by reproductive hormone disorders.