The Nilo Frantz Reproductive and Research Center provides a new exam technique for embryos which can double the chances of a successful artificial fertilization. It is called Comparative Genomic Hybridization (aCGH). The team in the Embriology Laboratory is working to develop a technique to analyze all 23 pairs of chromosomes in order to diagnose many genetic abnormalities which cannot currently be identified. The Center is a pioneer in the South of the country in terms of Preimplantation Genetic Diagnosis (PGD) with lasers, which can be used to genetically analyze embryos with the FISH (Fluorescence in situ hybridization) method before transferring it to the uterus. The PGD allows us to identify anomalies in some of the chromosomes, such as 13, 16, 18, 22, X, Y and 21, the last of which is responsible for Down's syndrome. The hybridization technique aims to increase the chances of pregnancy, especially in women over 35 years old, an age range in which the chances of getting pregnant decrease and the chances of genetic abnormalities, malformations and miscarriages increase.
This process will radically improve pregnancy rates in the near future. The new hybridization technique allows us to verify the 46 chromosomes in the pre-embryos from the 5th to 6th day after fertilization. Thus, we can transfer only the unaffected embryos to the uterus of the future mother. These cells are tested for different genetic illnesses - such as cystic fibrosis, Duchene muscular dystrophy and Huntington's disease. The analysis can only be done with couples who choose to have in vitro fertilization with preimplantation genetic diagnosis (PGD). With PGD the embryos are evaluated before they are transferred to the mother's uterus (before gestation).
Essentially, there are two laboratorial components in PGD. The first is related to collecting the material that will be analyzed, which is obtained through biopsy of an embryo. The second is the diagnostic test itself, which is usually done through two methodologies: polymerase chain reaction (PCR) or fluorescence in situ hybridization (FISH). As a general rule, FISH is used for chromosomal defects and PCR is used for genetic defects. PGD has been successfully applied to identify 30 monogenic diseases, as well as detect chromosomal imbalances in families with a history of chromosomal translocations. Learn more about the recommendations and main diseases that can be diagnosed with PGD.