Intelligent Design Icon Intelligent Design

The Treasure Hunt Continues: More Uses for Non-Coding DNA

MaggertAldrich_LabBench-1.jpg

As we have noted many times, geneticists put the brakes on research when they concluded that much of the human genome was junk from our evolutionary past. The surge in discoveries of function in the junk has falsified their pessimism. Now, the smart money is on new and exciting purposes for that non-coding DNA.

Heterochromatin

That’s the spirit shown by two biologists at Texas A&M University (pictured above) who are trying to unlock the non-coding half of the human genome, looking for understanding:

An obscure swatch of human DNA once thought to be nothing more than biological trash may actually offer a treasure trove of insight into complex genetic-related diseases such as cancer and diabetes, thanks to a novel sequencing technique developed by biologists at Texas A&M University.

The game-changing discovery was part of a study led by Texas A&M biology doctoral candidate John C. Aldrich and Dr. Keith A. Maggert, an associate professor in the Department of Biology, to measure variation in heterochromatin. This mysterious, tightly packed section of the vast, non-coding section of the human genome, widely dismissed by geneticists as "junk," previously was thought by scientists to have no discernable function at all. (Emphasis added.)

Mutations in those non-coding regions of heterochromatin, they believe, may contribute to diseases like cancer and diabetes. This suggests that those regions are doing something important.

Meanwhile, news from Brandeis University about heterochromatin is a bit humorous. Reporter Leah Burrows tries to hang onto her junk jewelry:

Scientifically speaking, there is no bad DNA, though we like to blame it for unruly hair, klutziness or poor gardening skills. There is, however, junk DNA.

The trouble is that the gene discussed in the article, named Med26, was found to reside in "junk" heterochromatin. An "entirely new role" for it was found by Michael Marr, associate professor at Brandeis. "It looks as though Med26 is tethered to the silencer and maybe activates essential genes that got lost in the junk pile," he said.

This casts doubt on whether anything was lost in a junk pile at all; Marr may have stumbled onto a new function for keeping essential genes around in a silenced state within heterochromatin, so that they can be reclaimed as needed. "Med26 is essential for multicellular life and is involved in both active and silent genes," Marr says. "Exactly how is the next big question."

Maybe an ID perspective would help.

Micro-RNA

Micro RNAs are coded in DNA and transcribed, but not translated into proteins. Since their functions have been largely unknown, it was easy to consider them cellular flotsam. But now UC San Diego announces an important function for a particular micro-RNA; it plays a "surprising role in cell survival," the article says.

Researchers at the University of California, San Diego School of Medicine have identified a microRNA molecule as a surprisingly crucial player in managing cell survival and growth. The findings, published in the October 7 issue of Cell Metabolism, underscore the emerging recognition that non-coding RNAs — small molecules that are not translated into working proteins — help regulate basic cellular processes and may be key to developing new drugs and therapies.

This particular micro RNA called let7 appears to regulate autophagy, the "self-eating" phase that cells enter under stressful conditions or the need to recycle materials. Finding this function may lead to better treatments for cancer.

Long Non-Coding RNA

One more example should suffice. A news item from Mary Anne Liebert publishers says that long non-coding RNAs (another class of RNAs transcribed but not translated into protein) "fine-tune the immune system."

Regulation of the human immune system’s response to infection involves an elaborate network of complex signaling pathways that turn on and off multiple genes. The emerging importance of long noncoding RNAs and their ability to promote, fine-tune, and restrain the body’s inflammatory response by regulating gene expression is described in a Review article in Journal of Interferon & Cytokine Research (JICR), a peer-reviewed publication from Mary Ann Liebert, Inc., publishers. The article is available free on the JICR website.

The paper has the forward-looking title, "Transcription of Inflammatory Genes: Long Noncoding RNA and Beyond." It suggests many more discoveries are waiting in the wings.

There’s a gold rush on, in search of treasure in "junk DNA." It’s just regrettable that biologists lost time thinking there was nothing there. Intelligent-design research would have expected that if something is there, there’s a reason for it, and if something works, it’s not happening by accident.

Image source: Texas A&M University.

Evolution News

Evolution News & Science Today (EN) provides original reporting and analysis about evolution, neuroscience, bioethics, intelligent design and other science-related issues, including breaking news about scientific research. It also covers the impact of science on culture and conflicts over free speech and academic freedom in science. Finally, it fact-checks and critiques media coverage of scientific issues.

Share

Tags

Junk DNAResearchScience