Α) Bone marrow transplant aid
In some cases of leukemia , bone marrow or stem cell transplants may be recommended. Choosing of a donor depends on the histo-compatibility of the recipient in order for the graft not to be rejected.
In bone marrow transplantation, high doses of chemotherapy or radiation are used to kill cancer cells, and also destroy all the normal cells in the bone marrow including important stem cells. After the treatment healthy stem cell are transplanted.
The most critical problem during transplants is to confirm that the recipient will not reject the donor bone marrow cells resulting in graft failure. The classical method (HLA matching) makes it hard to distinguish individuals that come from the same family (hematopoietic stem cell HLA matching/compatibility between the donor and the recipient)
- Genetic profiling distinguishes the individual DNA of brothers/sisters and relatives and therefore ensures that the graft is compatible (donor’s DNA only), if there will be a recurrence or a relapse or if the donor will reject the graft.
Β) Genetic profiling and prenatal screening
The prenatal diagnosis of genetic disorders such as β-Thalassemia, Cystic Fibrosis, Hemochromatosis etc involves the removal of foetus cells from the mother’s amniotic fluid (amniocentesis) or sampling of the chorionic villus. The removed foetal cells are grown, fixed and stained and under the microscope the chromosomes are examined. However this method can sometimes miss subtle abnormalities; if the quality of the cells is not good, then the complete absence of the mother’s tissue from the foetal cells cannot be confirmed. A mixture of the mother’s and the foetal’ cells could lead to incorrect positive or negative results and therefore a false diagnosis.
- Genetic profiling allows the separation of the mother’s DNA from the foetal’ DNA and therefore assures the accuracy of the test (sampling).
The use of genetic profiling in prenatal screening is important in order to confirm the high quality of the results.
C) Genetic profiling and twin embryos
The diagnosis of monozygotic twins (twins that come from a single egg) or dizygotic twins (twins that come from two different eggs) is important to detect genetic disorders of the foetuses or dysplasia in utero, as it determines the doctor’s decision.