Atlanta Preimplantation Genetic Diagnosis
Testing Embryos for Genetic Diseases
We are often able to determine if a particular embryo is carrying a specific
genetic disease. Through preimplantation genetic diagnosis (PGD), an embryo
developed during the
IVF process can be biopsied and the removed cells can be analyzed for a specific
genetically transmitted disease. This enables patients to greatly reduce
the likelihood of passing on a genetic mutation to their offspring.
Partial List of conditions that PGD can detect:
- Cystic Fibrosis
- Duschenne Muscular Dystrophy
- Retinitis Pigmentosa
- Charcot-Marie-Tooth Disease
- Alpha-1-Antitrypsin Deficiency
- Down's Syndrome
- Fragile X Syndrome
- Lesch-Nyhan Syndrome
- Turner Syndrome
- Huntington's Chorea
- Phenylketonuria (PKU)
- Gaucher's Disease
- Sickle Cell
How is PGD Performed?
PGD testing is performed on embryos that result from in vitro fertilization.
Multiple eggs are retrieved from the ovaries and fertilized with the partner's
sperm in our lab using a technique called
ICSI. Five to six days after fertilization, when each surviving embryo, now
called a blastocyst, contains hundreds of cells, 4 to 6 cells are removed
from the trophectoderm (placental cells) through a procedure called embryo
biopsy. The biopsied cells are then sent to a specialized lab for genetic
analysis using various techniques. The blastocysts themselves are frozen
after biopsy while we await the results of the genetic testing. Those
that show no abnormalities can be thawed in the next cycle during a frozen
embryo transfer. Frequently, PGD and PGS are performed in unison on embryos.
Who Should Have PGD?
PGD has revolutionized the management of patients at risk for passing on
an inherited genetic disease due to a single gene defect. PGD dramatically
improves the odds of having a baby without the disorder since affected
embryos are identified and not transferred. Some disorders only affect
male offspring, so that female embryos may be selected to avoid the condition
even if the exact defect isn't understood. Please
call our office to learn more about these exciting clinical tools.