Some ICSI sons could inherit fathers' infertility

Genetic studies at the Whitehead Institute for Biomedical Research have shown that some boys will be infertile as adults because they have inherited a genetic defect from their fathers through a commonly used method of assisted reproduction known as intracytoplasmic sperm injection (ICSI). It is known that many forms of male infertility have genetic origins.

Deletions on the Y chromosome - in particular a region known as AZFc - appears to account for infertility in about 10% of those men who produce inadequate amounts of sperm. Involving the injection of single sperm cells into individual eggs during standard in vitro fertilisation (IVF), ICSI is ideal for men with Y chromosome deletions (and therefore low sperm counts) because it only requires a few sperm cells.

However in a study published in the July issue of Human Reproduction, Dr Page and colleagues at the Whitehead Institute examined the sons of three men who had a deletion in the AZFc region and who had also undergone ICSI. In all three cases the sons possessed the same Y chromosome deletion as their fathers. Although clinicians had considered this to be a possible consequence of ICSI, this study is the first attempt to prove the hypothetical concerns.