How Placentas Evolved in Mammals
Published:22 Aug.2022 Source:University at Buffalo
In a new study, scientists use gene expression patterns, called transcriptomics, to investigate the ancient origins of one organ: the placenta, which is vital to pregnancy. They use gene expression patterns to reconstruct the evolution of the placenta and predict what the placenta of the last common ancestor of eutherian mammals looked like. their data showed that the placenta was invasive, and that non-invasive placentas evolved multiple times among mammals. This addresses a 150-year-old mystery: People have been debating what kind of placenta the first one was since then.
The study included about 20 species, such as the egg-laying platypus, pouch-bearing marsupials, and a range of eutherian mammals that give birth to live young. The small subset is one limitation of the analysis. Nevertheless, the study makes important contributions in understanding how pregnancy evolved. The results could also benefit modern medicine. Knowing which genes are active among different species during pregnancy could tell us about how evolution works. Moreover, it can also tell us about what makes a healthy pregnancy, and how things might go wrong. Scientists are finding the genes that establish the right kind of environment for healthy human pregnancies. If those genes are not expressed in the right way, that might give rise to problems.