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| Skip Sterling for Quanta Magazine |
Note: I'm in a process integration class for work, August 20 and 21st. I will also take some time offline to celebrate my youngest son's 23rd birthday. Taking a "human" break celebrating my own version of new genes; resuming Monday.
Emerging data suggests the seemingly impossible — that mysterious new genes arise from “junk” DNA.
Genes, like people, have families — lineages that stretch back through time, all the way to a founding member. That ancestor multiplied and spread, morphing a bit with each new iteration.
For most of the last 40 years, scientists thought that this was the primary way new genes were born — they simply arose from copies of existing genes. The old version went on doing its job, and the new copy became free to evolve novel functions.
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| Olena Shmahalo/Quanta Magazine; source: Tautz and Domazet-Lošo, _Nature Reviews Genetics_, 2011. New genes appear to burst into existence at various points along the evolutionary history of the mouse lineage (red line). The surge around 800 million years ago corresponds to the time when earth emerged from its “snowball” phase, when the planet was almost completely frozen. The very recent peak represents newly born genes, many of which will subsequently be lost. If all genes arose via duplication, they all would have been generated soon after the origins of life, roughly 3.8 billion years ago (green line). |
Certain genes, however, seem to defy that origin story. They have no known relatives, and they bear no resemblance to any other gene. They’re the molecular equivalent of a mysterious beast discovered in the depths of a remote rainforest, a biological enigma seemingly unrelated to anything else on earth.
Quanta Magazine: A Surprise Source of Life’s Code, Emily Singer
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