What can be offered to couples at (possibly) increased genetic risk?

Abstract

We review the reasons why a couple might seek specialist genetic counselling about a possible reproductive risk and the options available to them. Most commonly, the couple will be concerned about the risk of recurrence of a medical condition that has already occurred in the family. Sometimes, the increased risk may come from their ethnicity or because of a consanguineous marriage, rather than because any problem has occurred previously. The geneticist must identify the exact nature of any problem and determine the risks in the light of the mode of inheritance, any investigations undertaken and any other relevant information. The geneticist will then review the options open to the couple, and help them arrive at their own decision in a non-directive way. Some couples may opt to do nothing and let nature take its course but others may request prenatal or pre-implantation diagnosis, or they may avoid the conception of an at-risk child by using donor gametes, adoption or even decide not to have children.

Fig. 1

The importance of not forgetting germ-line mosaicism. As discussed in the text, recurrence risks in this family are very different depending whether the condition is autosomal recessive or autosomal dominant with the father being a germ-line mosaic