|
|
PGD - Preimplantation Genetic Diagnosis |
|
|
A very new and high technology for detection of abnormal
embryo is now available at our center , called
Preimplantation Genetic Diagnosis ( PGD ).
Following ovarian stimulation , egg collection and
fertilization, embryos are cultured for another 2 days
which they usually consist of 6-8 cells. Each of these
cells has complete genetic information and also each
cell has the potential to continue growth to establish
pregnancy. Therefore, one or two cells can be removed
from an 8-cells embryo by using an embryo biopsy
procedure and the embryo will continue to develop
normally. The removed cells will then be analyzed by
using a technique called Fluorescent in situ
Hybridization ( FISH ) or Polymerase Chain Reachion (
PCR ). The FISH technique can tell us whether an embryo
cell has two X chromosomes ( female ) or one X and one Y
chromosome ( male ) and FISH can also be used to detect
specific chromosome problems such as Down syndrome. FISH
analysis can give us the results within one day and the
resulting normal embryos will be transferred back into
the uterus.
This technique is now suitable for specific couples such
as advanced maternal age who have a very high risk to
have a child with Down syndrome , carriers of genetic
disease , recurrent abortion and couples who carry
X-linked diseases. Haemophilia and Muscular dystrophy
are examples of X-linked diseases.
In the future it is likely that genetic testing of
embryos will be used more routinely to improve IVF
success rates as well as to prevent transmission of
genetic disease. With the transfer of genetically normal
embryos, a higher percentage of implantation and reduced
miscarriage rates can be expected. |
| |
|
|
|
|
|
