As the genetic junk pile shrinks, and the treasure chest grows, it’s worth considering what happened to so-called "jumping genes" since we last looked at them in 2012 and 2013. These were considered part of "junk DNA" by geneticists disinclined to look for function in something they didn’t fully understand. Consisting of repetitive elements, called "Alu" sequences, jumping genes can move freely around the genome, but code for no proteins. What could they possibly be doing?

News from the University of Geneva shows that geneticists have changed their minds about these jumping genes. The "junk DNA" label is in their rear-view mirror:

"Alu" sequences are small repetitive elements representing about 10% of our genome. Because of their ability to move around the genome, these "jumping genes" are considered as real motors of evolution. However, they were considered for a long time as "junk" DNA, because, although they are transcribed into RNA, they encode no proteins and do not seem to participate actively in the cell’s functions. Now, the group of Katharina Strub, professor at the Faculty of Science of the University of Geneva (UNIGE), Switzerland, has uncovered two key functions of Alu RNAs in human cells, which are the subject of two different articles published in Nucleic Acids Research. Alu RNA can bind to specific proteins forming a complex called Alu RNP. On the one hand, this complex allows the cells to adapt to stress caused for example by chemical poisoning or viral infection. On the other hand, the same complex plays a role in protein synthesis by regulating the number of active ribosomes, suggesting that it could be part of the innate system of cellular defense against certain viruses. [Emphasis added.]

Those functions sound important. How could they arise from short sequences that don’t make proteins? The answer is that they bind with proteins, forming Alu RNP complexes. Those complexes increase when the cell becomes stressed by toxins or viruses. Why?

Under these conditions, the cell sequesters important signaling proteins into "stress granules." The Alu RNP complexes "actively participate in stress granule formation and dissolution." When the stress subsides, the cell produces a lot of Alu RNP that unlocks the proteins in the granules, allowing protein synthesis to resume.

These "jumping genes" also help protect from viral attacks. Viruses penetrating a cell start to hijack the protein synthesis machinery (ribosomes) "to their own profit." But the cell has an internal defense mechanism:

Based on the second study of the research group, Alu RNP complexes also play a protective role in case of infection. "They interfere with the formation of viral proteins, by inactivating the ribosomes before they are recruited to the viral RNA via the IRES", explains Elena Ivanova, researcher and first author of the second article. The cells in which Alu RNA expression increases following certain types of infection would thus produce a lot fewer viral particles.

Alu sequences thus appear to be part of the innate cellular defense against viral attacks: "These complexes are also used by cells to adapt to conditions of stress and they play a role in the process of protein synthesis, by regulating the number of active ribosomes."

This all sounds intelligently designed, so how do evolutionists explain it? They merely assert that evolution is a "function" of repetitive elements:

Having emerged within mammals from a common ancestor, the genomic "Alu" elements multiplied during evolution to the point of representing about 10% of the primate and human genomes, whereas they are about ten-fold less abundant in rodents. These small repetitive elements are an important source of genetic variations, due to their ability to move freely around the genome, and they are therefore considered as motors of evolution.

That’s a clever rhetorical strategy: call it evolutionary junk at first; then when functions are found, call it a "motor of evolution." No wonder evolution is a "fact" to Darwinians. They can’t lose. If it’s junk or treasure, Darwinian evolution made it.

Image: � MPerez / Dollar Photo Club.