TWIV is short for This week in Virology and is a podcast I have been listening to for years. Hosted by Vincent Racaniello it covers any thing related to viruses and this episode with Cedric Feschotte specifically explore the latest research on horizontal gene transfer which Cedric is calling mobile DNA.
Horizontal gene transfer is now considered a key part of the process of evolution and during the episode of around 6:22 Cedric introduces the Genomic shock idea from Barbara McClintock that species under stressful conditions can adapt their genome.
I have always felt that it was logically possible for an organism to encode something into its dna as this would provide an advantage for its offspring in continuing the line of succession and circle of life. Things like where to find water and nutrients and things to avoid like snakes or patterns of behaviour. All of these attributes are innate in species and given them an advantage.
Cedric also discusses the idea that viruses and mobile DNA could bring benefits to the host organism and that it may be necessary to have a certain amount of Mobile DNA to survive. As a software developer it is common practice to borrow or adapt code from other sources to fit the needs of a project and while it seems quite an incredibly complex thing for DNA to do it would clearly have an evolutionary advantage particularly in passing on traits and information to descendants either about hazards to avoid like snakes and spiders or ways to find water. When you also consider the relatively short life and fast reproductive cycle of bacteria and other organisms then it would make sense that groups of organisms could simple encode the required information into their DNA as a guide for the next generation and those with the best information end up surviving and passing on this ability. Later on larger organisms with slower reproductive cycles benefit.
My theory related to this which I have to put down in words came from the knowledge of writing software and relating this to the process of managing DNA. I had a logical concept about explaining how someone could have a memory from the oast before they were born that came from an ancestor.
It is well known that bacteria communicate through chemical messages and use a complex quorum sensing process to communicate and even hunt. Therefore they have complicated mechanisms for encoding and sharing information. RNA is also used when required to solve problems for the organism. Similar skills are used in software to turn sensory stimuli into code that can be stored as an image. We don’t think of it but this is basically a digital memory that we are used to sharing. Through the combination of the various coding technologies that bacteria, viruses and other organisms have it is plausible to me that organisms could share code that represents a memory and save that in DNA and potentially in the gametes that become offspring. If it confers an advantage then nature has a way of making this happen and what we now know of DNA processing in nature the tools are very much in place.
A new route to evolution: How DNA from our mitochondria works its way into our genomes: Scientists have shown that in one in every 4,000 births, some of the genetic code from our mitochondria—the ‘batteries’ that power our cells—inserts itself into our DNA, revealing a surprising new insight into how humans evolve.