Rescuer siblings are children who are supposed to help an older sibling who is ill. They act as a kind of archetype sibling, which is why this method is highly controversial. If a child needs blood or tissue, this can be taken from the “savior sibling,” who must be a genetic match to the sick child. To ensure the genetic match, artificial insemination is performed and the “optimal” embryo is implanted in the woman.
What are savior siblings?
Savior siblings as a medical method are ethically very controversial and banned in Germany, for example, but in the UK it is allowed, which is why affected parents seek help abroad. A person suffering from leukemia, for example, is dependent on foreign bone marrow and blood. It is usually difficult to find a suitable donor. In such a case, it is already permitted in some countries to “breed” a donor child. If the HLA compatibility of the parents of a sick child is insufficient, a sibling can be conceived by means of in vitro fertilization, i.e. in a test tube. The resulting embryos are then tested for their genetic match to the potential sibling, implanted into the woman’s uterus if compatibility is high, and carried to term during a normal pregnancy. The resulting baby then serves as a matching donor for the older brother or sister through their umbilical cord blood or bone marrow. Savior siblings as a medical method are ethically very controversial and banned in Germany, for example, but in Great Britain it is allowed, which is why affected parents seek help abroad.
Function, effect and goals
Preimplantation genetic diagnosis (PGD) is used to test the compatibility of artificially created embryos. PGD actually serves as a test to screen embryos from artificial insemination for hereditary diseases when the child’s parents are already pre-disposed. In the case of the savior siblings, it is used to find a possible donor. Vital cells for the older child can then be taken from the umbilical cord blood and bone marrow of the savior sibling, or saviour sibling. For this purpose, stem cells from the hematopoietic tissue are transplanted into the leukemia patient so that regular hematopoiesis can be restored. Unfortunately, only a few diseases can be treated in this way so far. A suitable bone marrow donor is also needed for some forms of anemia, where savior siblings can replace blood transfusions from strangers. Organ donations from rescuer siblings, on the other hand, are more critical because they carry a high risk for the donating child. Parents of savior siblings usually refrain from such donations, as this exposes one child to particular risk in order to save the other. In 2003, the first genetically selected savior sibling in Europe was born in the United Kingdom. PGD is permitted throughout Europe except in Germany, Austria and Switzerland.
Risks, side effects, and dangers
In Germany, no savior siblings may be created, especially embryo selection, which is common in PGD, is prohibited in principle. It is prohibited under the German Embryo Protection Act to grow embryos for anything other than pure pregnancy. Of particular concern seems to be the possibility of creating a “designer baby.” Being able to determine the hair and eye color of one’s child, whose nose it will have, or how tall it will be. Even as a medical treatment method, fishing for the best genes is questionable, as the created sibling might feel more like an expedient child than a desired one. Nevertheless, it should be noted that another child’s life can be saved in this way. In 2010, a little girl in Bristol, UK, was cured of her Fanconi anemia with the help of stem cell therapy. Her little brother had been selected from several embryos for this reason a few months earlier. However, it is not only the psychological consequences for the children that need to be considered, but also the risks associated with artificial insemination. The egg is surgically removed from the woman, which is why she is exposed to the usual risks such as infection or internal injuries. Basically, artificial insemination is often followed by a high-risk pregnancy, up to and including miscarriage.
