P-020 Analysis of cystic fibrosis transmembrane regulator (CFTR) gene mutations in men with congenital agenesis of vas deferens

considered an equally reliable but inexpensive and noninvasive alternative method of monitoring ovulation in relation to endometrial development in protocols for the development of alternative contraceptive strategies. The finding that the defined LH peak occurred after ovulation in 8.47% of volunteers deserves further investigation.

M o n d a y , October 20, 1997

Male Infertility P-020 Analysis of Cystic Fibrosis Transmembrane Regulator (CFTR) Gene Mutations in Men with Congenital Agenesis of Vas Deferens. B. Thamm, S. Strenge, H. Reichenbach, D. Wand, U. G. Froster. Institute of Human Genetics, Leipzig, Germany. Objectives: Cystic fibrosis (CF) is one of the most common autosomal recessive genetic disorders in the Caucasian population. Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene have been detected in patients with CF and in males with infertility attributable to congenital bilateral absence of the vas deferens (CBAVD). CBAVD is present in 1-2% of the infertile but otherwise healthy male population and accounts for at least 6% of cases of obstructive azoospermia. Design: We examined clinical features and mutation data obtained in the genetic screening for CFTR mutations in eight unrelated men and their female partners who were referred for genetic counselling because of a planned in-vitro fertilisation (IVF). Three of the male patients were affected by CBAVD, five by severe oligozoospermia and presumed congenital unilateral absence of vas deferens (CUAVD). None of the patients showed pulmonary or gastrointestinal manifestations typically for CF. In four cases intracytoplasmic sperm injection (ICSI) is planned, in one case a pregnancy was successfully established with ICSI. Materials and Methods: Polymerase chain reaction (PCR) was used to amplify exons 4, 7, 10, 11, 20, 21 and part of the intron 19, followed by allele specific oligonucleotide hybridisation, restriction enzyme digestion or direct sequencing to estimate the mutations deltaF508, deltaI507, G542X, G551D, R553X, 1717-1 (G~A), W1282X, N1303K, R347P, 3849+10kbC-~cG, R l l 7 H and Rll7C. Additionally the intron 8 poly(T) tract length was analysed using a nested PCR method. Results: Two of the three men with CBAVD were found to be carriers of CFTR mutations (R117H and R553X). In one of them the presence of the severe mutation R553X was associated with the 5T allele in intron 8, which is presumed to cause low level CFTR expression. One of the CBAVD patients did not have any of the investigated mutations; one of the presumed CUAVD patients was carrier of the mutation deltaF508. All men with detected CFTR mutations had normal to slightly increased sweat chloride concentrations. None of the investigated mutations could be found in the female partners.

S102

Abstracts

Conclusions: These first preliminary results indicate, that the analysis of CFTR gene mutations in men with obstructive azoospermia and severe oligozoospermia as well as the screening of their female partners for an incidental CFTR condition is critical for couples undergoing IVF procedures in order to predict the risk of a child affected by CF.

P-021 Testicular Sperm Distribution in Azoospermia. 1S. J. Silber, 2H. Tournaye, 2A. Goossens, 2p. Nagy, ~P. Devroey, 2A. C. Van Steirteghem. 1Infertility Center of St. Louis, St. Luke's Hospital, St. Louis, MO, USA and 2Centre for Reproductive Medicine, University Hospital, DutchSpeaking Free University, Brussels, Belgium. Objectives: Men with non-obstructive azoospermia caused by germinal failure can now be treated successfully in some cases using testicular sperm extraction (TESE) and ICSI. We wished to determine whether a prior diagnostic testicle biopsy analyzed quantitatively can predict success or failure of TESE-ICSI. We also wished to determine what is the threshold of quantitative sperm production in the deficient testis, below which no sperm will reach the ejaculate (azoospermia). Method: Forty-five patients with non-obstructive azeospermia caused by testicular failure underwent diagnostic testicle biopsy prior to a subsequent TESE-ICSI procedure. The diagnostic testicle biopsy was analyzed quantitatively, and correlated to the results of subsequent attempts at TESE-ICSI. Results: Men with non-obstructive azoospermia caused by germinal failure had a mean of zero to 6 mature spermatids per seminiferous tubule seen on a diagnostic testicle biopsy. This compared to 17 to 35 mature spermatids per tubule in men with normal spermatogenesis and obstructive azoospermia. These findings were the same for all types of testicular failure whether Sertoli cell only, maturation arrest, cryptorchidism, or post-chemotherapy azoospermia. The results of subsequent TESE-ICSI procedures are summarized below: # Patients With or Without Mature Spermatids Found on Histology

# Patients With Sperm # Pregnant Found at (Ongoingor TESE-ICSI Delivered)

With Sperm Without Sperm

26 19

22 (85%) 1 (5%)

12 (55%) 0 (0%)

Total

45

23 (51%)

12 (52%)

Conclusions: In order for any sperm to reach the ejaculate, greater than 6 mature spermatids must be present in a section of testis; 2) Prior diagnostic testicle biopsy analyzed quantitatively is extremely useful for predicting which patients will have success or failure with TESEICSI; 3) Incomplete testicular failure appears to involve a sparse multi-focal distribution of spermatogenesis