Non-disclosing preimplantation genetic diagnosis for Huntington disease.

OBJECTIVES Individuals at risk for Huntington disease face difficult decisions regarding their reproductive options. Most do not wish to pass on the gene for Huntington disease to their children, but may not be prepared themselves to undergo presymptomatic testing and learn their genetic status. For these reasons, many at-risk individuals with a family history of HD would choose a method of genetic diagnosis that would assure them that they can have children unaffected with HD without revealing their own genetic status (non-disclosing). We have shown that, with a carefully designed and executed programme of non-disclosing preimplantation genetic testing, one can successfully assist at-risk couples to have their own biological children who are free from Huntington disease, without forcing parents to confront knowledge of their own genetic status. METHODS Couples where one partner was at 50% risk for Huntington disease underwent in vitro fertilization with preimplantation embryo biopsy and molecular analysis for Huntington disease where appropriate. RESULTS After extensive counselling and informed consent, 10 couples underwent 13 in vitro fertilization and two frozen embryo transfer cycles in a programme for non-disclosing preimplantation genetic diagnosis for Huntington disease. In 11 cycles, embryos determined to be free of Huntington disease were transferred, resulting in five clinical pregnancies. One set of twins and three singleton pregnancies have delivered. One pregnancy resulted in a first-trimester loss. CONCLUSIONS The option of non-disclosing preimplantation genetic diagnosis should be reviewed, along with other relevant medical options, when counselling at-risk Huntington disease families.