Carrier testing

Testing an individual to establish his or her carrier state for an
autosomal or X linked recessive condition or chromosomal
rearrangement, will usually be for future reproductive, rather
than health, implications. Confirmation of carrier state may
indicate a substantial risk of reproductive loss or of having an
affected child. Genetic counselling before testing ensures that
the individual is informed of the potential consequences of
carrier testing including the option of prenatal diagnosis. In
the presence of a family history, carrier testing is usually
offered in the mid-teens when young people can decide
whether they want to know their carrier status. For autosomal
recessive conditions such as cystic fibrosis, some people may
wish to wait until they have a partner so that testing can be
done together, as there will be reproductive consequences only
if both are found to be carriers.