Genetic counselling

The counsellor role is to present facts concerning the problem to the parents and enable them making a conscious decision. Majority of consulting persons have an ill person in the family or have ill children. They want to know what is the risk for next pregnancies and what are their possible choices.

Counselling is based on diagnosing the disease, construction of pedigree and calculating the risk of having ill baby. Often also probability for parent to be a carrier must be calculated. Calculations takes advantage of calculus of probability, especially Bayes theorem (conditional probability)

The counsellor describes the situation will the disease occur (prognosis, curing) and possible choices. Parents can accept the risk, decide on artificial insemination with a sperm form a stranger (when father has autosomal dominant disease or both parents are carriers of a serious recessively inherited disease), decide on pregnancy with possibility of selective abortion if foetus has the disease (when disease can be prenatal diagnosed) or adopt a child.