What's pre implantation genetic diagnosis and it's function?

Answer 1

Preimplantation Genetic Diagnosis (PGD) is a reproductive technology used in conjunction with in vitro fertilization (IVF) to screen embryos for specific genetic conditions before they are implanted in the uterus. The procedure involves several key steps:

1. Ovarian Stimulation: The woman undergoes hormonal treatment to stimulate her ovaries to produce multiple eggs.

2. Egg Retrieval: Once the eggs are mature, they are retrieved from the ovaries.

3. Fertilization: The retrieved eggs are fertilized with sperm in a laboratory setting to create embryos.

4. Embryo Development: The embryos are cultured for several days (usually 3-5 days), allowing them to develop.

5. Biopsy: A few cells are carefully removed from each embryo. This is typically done on day 5 when the embryos reach the blastocyst stage.

6. Genetic Testing: The extracted cells undergo genetic testing to identify specific genetic abnormalities or conditions, such as chromosomal disorders or single-gene diseases.

7. Selection of Healthy Embryos: Based on the results of the genetic testing, the embryos that do not carry the genetic condition can be selected for transfer into the uterus.

8. Embryo Transfer: The selected healthy embryo(s) are then implanted into the woman’s uterus in hopes of achieving a successful pregnancy.

Functions of PGD:

• Prevention of Genetic Disorders: PGD allows for the identification of embryos at risk of specific inherited conditions, enabling parents at risk of passing on genetic diseases (such as cystic fibrosis, sickle cell anemia, or Tay-Sachs disease) to choose healthy embryos.

• Reduced Miscarriage Rates: By selecting embryos with normal genetic profiles, PGD may help reduce the likelihood of miscarriage associated with genetic abnormalities.

• Increased Success Rates of IVF: PGD can enhance the chances of successful implantation by selecting the most viable embryos, thereby potentially improving overall success rates of IVF treatments.

• Family Planning: For couples with known genetic disorders, PGD offers a way to have children who are not affected by those conditions and helps them make informed decisions about family planning.

PGD is a powerful tool in reproductive medicine, but it also raises ethical considerations regarding genetic selection, the potential for "designer babies," and the psychological implications for families undergoing the process.