Karyomapping looks at the chromosomes, the rod-like structures that are found in cells and contain the genes. Karyomapping examines the chromosomes of the mother, father and the reference (which is another person with the condition in another generation) at 300,000 different points, looking for features characteristic of the defective chromosome. Essentially, karyomapping finds a fingerprint that is unique to the chromosome that carries the defective gene. It is then possible to test embryos produced using IVF for the presence of this fingerprint. Whenever the fingerprint is seen in an embryo, it means that it has inherited the chromosome carrying the defective gene.
Due to the large amount of information obtained, the preparation time required before treatment is reduced to a few weeks, from the several months (or sometimes many months) which it used to take before this technique was available. The power of this technology is that it offers help to couples at risk of more than one genetic disorder, testing for both simultaneously. In addition, karyomapping screens for chromosomal abnormalities, which could cause miscarriage or developmental abnormalities, so that the pregnancy outcome is improved. Carrying out more than one test at the same time was previously too technically demanding on such a small sample of DNA.
By obtaining a blood sample from the couple and another close relative, the Clinic is able to prepare a diagnosis in a matter of weeks.
If you are interested, ask for a referral from your neurologist, or geneticist (might even be worth asking your GP) and after ensuring that you are a suitable candidate, you will be referred to the Clinic in London – and there is a minimal waiting time.
For further information, please email Karen Doye, Lead PGD Nurse – Karen.firstname.lastname@example.org – Karen is based at the Centre for Reproductive and Genetic Health in London.