Several things have been noted in this year’s science magazines—things about genes that we should keep in mind when considering alien life possibilities.
In the Arctic’s 1.8 million year-old mud, there has been found a new phylum called Lokiarchaeota. It has genes similar to both our eukaryotic cells and ancient archaea cells. This is another gem of bio-information that illustrates the variety that chemical building blocks can take.
As a result, the evolutionary tree of life has been revised once again. In fact it’s no longer a tree (according to Journal Eukaryotic Microbiology 2003). It’s a circle of life, with bacteria, eukaryotes and archaea sprouting off at intervals with shared characteristics
Then there is gene regulation. What turns them off and on? Where they are? What other genes are doing? What chemical priorities are active in that where and when? Molecular gene switches called ligands have been developed that can control how transplanted genes function. Such genes can code cells to produce a hormone that can trigger a process like moulting in insects. Giving a measured dose of hormone can control the extent of the gene’s activity.
Studies have shown that such fine control of genes’ “expressed” activity can be limited to certain tissues and/or under certain conditions. The ligand switches can control DNA directly or they can control gene activity at the RNA level. The lesson for treating cancer is that “..once the immune system is properly primed to take out one nest of cancerous cells, it should start searching for others elsewhere in the body…”
We have learned that the genes in fertilized eggs know from the beginning where they are, hence what they need to do. And now we have seen one human father hand down his mitochondrial DNA to his off spring, as some plants and sheep do. We can celebrate a talented mitochondria and look for exo-possibilities, but it sure does add “…confusion in maternal lineage, thus evolutionary relationships.”
Some cypress and yew trees have doubled their entire genomes, as did pine trees 342-200 million years ago, which may have saved them from the Permian-Triassic extinction.
Recently we have learned that CRISPR gene drives provide a quick and easy way to cut and paste any kind of gene from any kind of living thing to any other kind of critter. RNA may also be involved in the process. It’s easy to do, and it works with all kinds of life from yeast to rhesus macaques. The possibilities could be scary–or wonderful for life as we know it, if some horrendous diseases, like hemophilia, are eliminated.
The ease of the genetic trade-offs and controls we have identified lately bode well for thinking that the potential for life elsewhere is possible—except for one over-riding problem. It’s all complex, hence it takes (probably took and will take) a very long time to sort out what works best in a terribly diverse and often unique environment on this planet or that.
Author of The Archives of Varok
The View Beyond Earth (Book 1.)
The Webs of Varok (Book 2.)
Nautilus Silver Award 2013 YA
ForeWord IBPA finalist 2012 adult SF
The Alien Effect (Book 3.)
An Alien’s Quest (Book 4. coming in 2016)
Excerpts, Synopses, Reviews, On Writing, Characters and More-
Reviews of significant books- http://www.goodreads.com/Cary_Neeper
How the Hen House Turns- http://www.ladailypost.com
Complexity, Bio, Bibliography and Links- http://caryneeper.com
Astrobiology- http://astronaut.wpengine.com search:Who’s Out There