The mail aim of the present study is to use molecular methods to analyze the ability of human preimplantation embryos to repair their DNA

The main aim of the present study is to investigate the DNA repair pathways of preimplantation embryos, examining the events that take place following induction of a DSB at a unique targeted site. The investigators aim to address questions concerning the functionality of the DNA repair mechanism(s) in developing embryos, before and after genome activation.

Inclusion Criteria:

• gamete donors: be at least 21 years of age, in good health and eligible to donate their games through the standard gamete donation programs
• IVF couples: any couples proceeding with a routine IVF cycle

Exclusion Criteria:

• less than 21 years of age
• inability to provide informed consent

Healthy volunteer subjects will be recruiting from amongst the gamete donor population and patients undergoing in vitro fertilization (IVF) for treatment of their infertility