CHROMOSOME-ANOMALIES AND Y-CHROMOSOME MICRODELETIONS AS CAUSAL FACTORS IN MALE-INFERTILITY

Among the 10% or so of men who are diagnosed as oligo-or azoospermic i n the absence of any physical obstruction, research is now showing tha t between 8 and 15% carry a microdeletion in the long arm of the Y chr omosome which, by loss of specific DNA segments, leads to loss of vita l genes for sperm production. Chromosomal anomalies account for simila r to 2% of all men who attend infertility clinics, rising to 15% among those with azoospermia. There are serious implications for couples se eking help by intracytoplasmic sperm injection (ICSI), since chromosom al or gene defects which might normally be lost or eliminated by natur al means could be transmitted in offspring. The need for genetic testi ng of ICSI donors and their offspring is raised, and a requirement for counselling is recommended.