How Genetic Testing Is Used

Testing Embryos For Genetic Conditions

Amniocentesis

Fetal cells are collected

Can be carried out from 15 to 17 weeks

A needle is inserted into the amniotic fluid

Carries a 1% chance of miscarriage

Chorionic Villus Sampling

Can be carried out from 8 to 12 weeks

A small piece of placental tissue is removed

Carries a 1% - 2% chance of miscarriage

Non Invasive Prenatal Diagnosis

Analyses DNA fragments from blood plasma

Only around 20% of the DNA is from the fetus

Can be carried out from 7 to 9 weeks

Identifying Carriers

Confirming A Diagnosis

Used when there is a family history of CF

Counselling is provided before and after

Any abnormalities can be detected

Allows parents to make an informed decision

A sample of blood or cells is taken

There are many mutations that can cause CF

May be based on a sweat or cell test

A negative result must be treated with caution

It is currently impossible to test for all mutations

Genetic testing can confirm an initial diagnosis

Although 1 in 25 people in the UK carry the Cystic Fibrosis gene, many do not know until they have a child with the disease. Once CF is suspected, there are conventional tests that can be done, to confirm the diagnosis. People suffering from CF have elevated levels of the protein trypsinogen in their blood, which can be tested for. Testing for this protein is part of the Newborn Blood Spot Screening Programme, for all babies born in the UK. An early diagnosis of CF allows treatment to begin immediately, which can be a great improvement to health in later life.