Scottish
Huntingtons Association Illustrated Pages
Frequently
Asked Questions
How Does Huntingtons
Disease Progress?
Three Catergories of Testing
A blood test is now available that can determine, in almost
all cases, whether a person has the HD gene.
This test cannot, however, predict when symptoms will begin or the course of
the disease. There are three
categories of testing:
Predictive Testing
Since the marker gene for HD was discovered in 1983 it has
been possible for an "at risk" person 18 years or over to have a
predictive test.
Deciding whether to have the predictive test is a very
personal choice. It needs to be considered carefully because the implications
vary for each person.
But you won't have to make the decision without support, as counselling is a
major part of the testing program.
Prenatal Predictive Testing
There is also a prenatal form of the predictive test for HD.
The purpose of prenatal testing is to screen the foetus in order to avoid
passing on the
HD gene to the next generation.
If the foetus is found to have a high risk of carrying the
HD gene termination of the pregnancy can be considered by the parents.
Pre-implantation Genetic Diagnosis
Pre-implantation genetic diagnosis is new form of prenatal
testing that utilises advanced reproductive technology. It avoids the need for
termination
of a pregnancy where the foetus has inherited the HD gene.
The testing involves creating embryos in vitro (in a test
tube). The embryos are then tested to see if they have the defective gene. Only
embryos
which do not have the defective gene are then implanted in the female partner
who it is hoped will become pregnant.
Scottish Huntingtons Association,
Thistle House, 61 Main Road,
Elderslie, PA5 9BA,
Tel; 01505 322245,
email: sha-admin@hdscotland.org.uk
The Scottish Huntington's Association is
a Registered Charity: No 121496.