Late-onset Disorders include adult diseases such as Alzheimer’s, Huntington's and heart disease.

One of the uses of PGD are the identification of embryos at risk for late-onset diseases. Late-onset Disorders are complex and have both genetic and environmental causes. Genetic tests may indicate a susceptibility or predisposition for these diseases. Diseases like Huntington's disease, are caused by single genes that also are seen later in life.

These types of disorders can be tested for at any time.

Preimplantation genetic diagnosis (PGD) technology allows genetic testing of human eggs and embryos before pregnancy making it completely realistic to establish only potentially normal pregnancies without Alzheimer's disease or any other late-onset disorder with a genetic predisposition.

With no current prospect for the treatment of Alzheimer's disease, prevention of an inherited predisposition to Alzheimer's is the only option for couples at risk.