Genome complexity: evidence of non-random mutation (Introduction)

by David Turell , Wednesday, February 02, 2022, 16:01 (808 days ago) @ David Turell

In Arabidopsis thaliana, or thale plants:

https://phys.org/news/2022-01-evolutionary-theory-dna-mutations-random.html

"Researchers spent three years sequencing the DNA of hundreds of Arabidopsis thaliana, or thale cress, a small, flowering weed considered the "lab rat among plants" because of its relatively small genome comprising around 120 million base pairs. Humans, by comparison, have roughly 3 billion base pairs.

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"'At first glance, what we found seemed to contradict established theory that initial mutations are entirely random and that only natural selection determines which mutations are observed in organisms," said Detlef Weigel, scientific director at Max Planck Institute and senior author on the study.

"Instead of randomness they found patches of the genome with low mutation rates. In those patches, they were surprised to discover an over-representation of essential genes, such as those involved in cell growth and gene expression.

"'These are the really important regions of the genome," Monroe said. "The areas that are the most biologically important are the ones being protected from mutation."

"The areas are also sensitive to the harmful effects of new mutations. "DNA damage repair seems therefore to be particularly effective in these regions," Weigel added.

"The scientists found that the way DNA was wrapped around different types of proteins was a good predictor of whether a gene would mutate or not. "It means we can predict which genes are more likely to mutate than others and it gives us a good idea of what's going on," Weigel said.

"The findings add a surprising twist to Charles Darwin's theory of evolution by natural selection because it reveals that the plant has evolved to protect its genes from mutation to ensure survival.

"'The plant has evolved a way to protect its most important places from mutation," Weigel said. "This is exciting because we could even use these discoveries to think about how to protect human genes from mutation.'"

Comment: It seems chance mutations can be protected from affecting plants. Was this designed or a natural event? I'll stick with design.