ASSISTED REPRODUCTIVE TECHNOLOGY AND COMPLEX CHROMOSOMAL REARRANGEMENTS - THE LIMITS OF ICSI

Complex chromosomal rearrangements are very rare events in the human p opulation. According to our knowledge on the consequences of simple re ciprocal translocations for male fertility, translocations involving t hree or more chromosomes are thought to lead to severe reproductive im pairments in terms of meiotic disturbance or chromosomal imbalance of gametes. We report the case of a 48 year old man whose sperm count rev ealed either oligozoospermia (<10(3) spermatozoa/ml) or azoospermia. H e was referred to the laboratory for in-vitro fertilization after intr acytoplasmic sperm injection. Cytogenetic investigations showed a comp lex chromosomal rearrangement involving firstly a translocation betwee n the short arm of chromosome 7 and the long arm of chromosome 13 and secondly a translocation between the short arm of the same chromosome 13 and the short arm of chromosome 9. Diagnosis was ascertained by flu orescence in-situ hybridization and staining of the nucleolar organize r regions. Theoretical study of the translocated chromosomes predicted a 'chain' configuration of the hexavalent at the pachytene stage of m eiosis. In all, 32 modes of segregation were considered and only one r esulted either in a normal or a balanced gamete karyotype. Genetic cou nselling and choice of appropriate artificial reproduction technique a re discussed.