Magic embryology: placenta like no other organ (Introduction)

by David Turell , Wednesday, March 10, 2021, 18:23 (1355 days ago) @ David Turell

Has many mutations and seems to screen for them:

https://medicalxpress.com/news/2021-03-placenta-dumping-ground-genetic-defects.html

"In the first study of the genomic architecture of the human placenta, scientists at the Wellcome Sanger Institute, the University of Cambridge and their collaborators have confirmed that the normal structure of the placenta is different to any other human organ and resembles that of a tumor, harboring many of the same genetic mutations found in childhood cancers.

"The study, published today in Nature, found evidence to support the theory of the placenta as a 'dumping ground' for genetic defects, whereas the fetus corrects or avoids these errors. The findings provide a clear rationale for studying the association between genetic aberrations and birth outcomes, in order to better understand problems such as premature birth and stillbirth.

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"It has long been known that the placenta is different from other human organs. In one to two percent of pregnancies, some placental cells have a different number of chromosomes to cells in the fetus—a genetic flaw that could be fatal to the fetus, but with which the placenta often functions reasonably normally.

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"'Our study confirms for the first time that the placenta is organized differently to every other human organ, and in fact resembles a patchwork of tumors. The rates and patterns of genetic mutations were also incredibly high compared to other healthy human tissues."

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"Professor Gordon Smith, a senior author of the study from the University of Cambridge, said: "It was fascinating to observe how such a serious genetic flaw as a chromosomal copy number error was ironed out by the baby but not by the placenta. This error would have been present in the fertilized egg. Yet derivative cell populations, and most importantly those that went on to form the child, had the correct number of copies of chromosome 10, whereas parts of the placenta failed to make this correction. The placenta also provided a clue that the baby had inherited both copies of the chromosome from one parent, which can itself be associated with problems."

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"Dr. Sam Behjati, a senior author of the study from the Wellcome Sanger Institute, said: "The placenta is akin to the 'wild west' of the human genome, completely different in its structure from any other healthy human tissue. It helps to protect us from flaws in our genetic code, but equally there remains a high burden of disease associated with the placenta. Our findings provide a rationale for studying the association between genetic aberrations in the placenta and birth outcomes at the high resolution we deployed and at massive scale.'"

Comment: Here again we see God saw need for error corrections and provided a mechanism.