(also see www.reproductivegenetics.com/preimplantation.php )
The PID or PGD as it is known in Anglo-American states, was originally developed as an alternative to Prenatal Diagnosis in which amniocentesis or chorionzotten biopsy was performed. About 70% of all miscarriages are due to genetic factors.
The Prenatal Diagnosis is only possible when a pregnancy is established, whereas PID / PGD is possible on the embryo before pregnancy.
The biopsy is performed by taking a single cell out of the embryo, usually on the 3rd day after fertilization in the 6-8 cell stadium. The single cell is examined using the Polymerase Chain Reaction (PCR) or Fluorescence In Situ Hybridisation (FISH) method.
PCR is used for single genetic defects. FISH on the other hand, is used for chromosome analysis to clarify sex-linked illnesses (x-linked disease), for chromosome abnormalities like translocation, and for the diagnosis of aneuploidien.
PID / PGD is not allowed in Austria, Germany, Italy and Switzerland, but it is possible in the Czech Republic.
The PID can also be used to do an HLA-Typing on the embryo to transfer it afterwards. These techniques can be applied, if there is a medical indication, for example a sibling suffering from a dangerous disease can be helped with cord blood of a baby (its borhter/sister), or Fanconi-Anemia, Leukemia, Auto-Immun diseases... . If the bone marrow gets destroyed by chemotherapy or radiation due to a malignant disease, then the sick kid's only survival chance would be to receive bone marrow from a sibling or a qualified donor to build up the marrow again.
Analysis of the 1st and 2nd Polkörperchen
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With the help of cytogenetic analysis of the 1st and 2nd Polkörperchen we can have an insight into the chromosomal status of the egg cell; Chromosomal "Aneuploidien" originating in the mother can be detected.
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Most chromosomal abnormalities are resulting from meiosis of the egg cell
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This is frequently connected to a higher age of the woman
Polkörperchenanalysis
Relation: Age - Pregnancy
Blastomere-Analysis
The biopsy is performed by taking a single cell out of the embryo (Blastomere), usually on the 3rd day after fertilization in the 6-8 cell stadium. The PID/PGD on blastomeres is currently allowed in the Czech Republic only.
Individual Consultation
In some cases, a specific analysis of the factors, that are causing fertility problems, is necessary. In this case, patients from the East of Austria can consult Dr. Thomas Fiedler (Specialist for Gynecology) in Linz, Upper Austria.
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