PGD for Single Gene Defects
Preimplantation Genetic Diagnosis for Single Gene Defects
PGD for single gene defects is used to analyze embryos when one or both aspiring parents carry a known genetic abnormality. The diagnosis aims to identify this particular abnormality, helping couples avoid a miscarriage and prevent the birth of a child with a disorder. The PGD for single gene defects is conducted as part of the IVF process, and is referred to as IVF-PGD.
This diagnosis is a blessing for couples with a genetic abnormality in the family. Prior to IVF-PGD, the only way to prevent the birth of an abnormal child was through prenatal diagnosis when the aspirant mother was already pregnant. While this practice identified the abnormality, if the gene defect was there, the only options were to either deliver and raise a child with the abnormality or to terminate the pregnancy.
Now, with preimplantation genetic diagnosis we can identify the abnormal embryos before the transfer to the uterus takes place. This provides a safe and effective way to prevent the conception of a child with a genetic abnormality and effectively reduces the likelihood of miscarriage.
How it Works
The preliminary stages of IVF-PGD are the same as that of the IVF treatment process. After the eggs are ripened, they are retrieved and then fertilized. The resulting embryos are grown and then frozen to perform the biopsy to identify any genetic abnormality. If an abnormal embryo is present, it’s singled out, and only the normal ones transferred to a frozen embryo cycle.
Normally, the biopsy is done on Day 5 of the fertilization. Our embryologist uses polymerase chain reaction (PCR) to identify the abnormal gene and comparative genomic hybridization (CGH) for finding its chromosome element. By magnifying the DNA in this way, the error rate is hugely diminished.
Warding off Numerous Genetic Diseases
From Huntington’s disease to cystic fibrosis to muscular dystrophy, there are hundreds of genetic diseases from which the PGD of IVF treatment process protects your future offspring. So if as a couple you carry a genetic condition, and are concerned about transferring it to your child, IVF-PGD can be the perfect solution. In addition to carrying a genetic abnormality, couples may also need the diagnosis under the following situations:
- An ethnic screening test comes out positive for one or both parents (e.g. cystic fibrosis for a Caucasian couple)
- Someone within the couple’s family requires compatible stem cells to survive, since embryos contain an advantageous genetic attribute (e.g. matching tissue type from an immediate family member)
- The mother carries an X-linked disorder. This disorder does not have a diagnosis as of yet, and affects 50% of male embryos. Hence, PGD is used to select female embryos to maximize the chances of a safe and successful pregnancy
As the best fertility specialist in Tucson, the Arizona Center for Reproductive Endocrinology & Infertility is proud of its expertise in IVF-PGD, through which we bring hope to couples and ensure the birth of healthier children.
Call Us Today
We will be glad to discuss your situation and fertility options at length and help you discover the most suitable solution for getting pregnant. Set up an appointment today by calling 520-326-0001.