PGD indications are quite similar to those practiced in prenatal diagnosis, i.e serious hereditary disorders that may result in a therapeutic abortion following prenatal diagnosis of an affected fetus. According to european recommendations, couples requesting information about PND may also be counselled about PGD, limits and errors related to PGD, as well as the possibility to perform PND to confirm PGD results.

The PGD procedure is applied to monogenic disorders, that are classified into three main categories :

- Autosomal recessive disorders : the mutant gene is inherited from both unaffected parents; the risk of having an affected child is therefore 25%. Cystic fibrosis, hemoglobin disorders, spinal muscular atrophy are common indications of PGD.

- Autosomal dominant disorders: the risk of having an affected child is 50% as a mutation in only one of the two gene copies is sufficient to cause disease expression. Examples : myotonic dystrophy, Huntington disease, familial polyposis coli, Charcot-Marie-Tooth disease, von Hippel Lindau disease, retinoblastoma….

- X-linked recessive disorders : 50% of male embryos may be affected. Examples : Duchenne muscular dystrophy, haemophilia...