Received December 22, 2005
Accepted May 15, 2006

The technology of assisted reproduction is a well established treatment for infertility. Consequently the number of children born after a treatment of assisted reproduction increased drastically in the last years in the whole world. As a result of that, researchers started to evaluate the potentials risks to the health and the development of the embryo when the techniques of ART are already used. In addition to the known risks of multiple gestation, several recent studies have shown a connection among the use of the reproduction techniques attended with rare disorders of genomic impression including the syndromes of Beckwith-Wiedemann, Prader-Willi and Angelman. In this study we revised some molecular mechanisms of genomic impression, considering as the treatment could infl uence the genomic impression of gametes and embryos.