Musings on Midi-Chlorians & Mitochondrial DNA

Like many Star Wars fans that I know, I really dislike the concept of Midi-Chlorians as put forward in the movies. However, as Lucas based many of his concepts in the film off of a variety of concepts already around us today, I couldn't resist putting a few thoughts about these tiny little microbes that Lucas came up with.

Midi-Chlorians are:

• what communicates to a being and to the Force,
  
• microbes that live in the cells of all living things
  
• essential to all life
  

With that explanation in mind I could only decide how reminiscent of theMitochrondrial DNA the concept is.

Mitochondrial DNA:

• communicates our genetic patterns to us
  
• are essential all living things because they are the cells power source
  
• are about the size of bacteria and have different shapes depending upon the type of the cell it is in
  

To understand why mtDNA are important it is key to realize that it is these mitochondria that provide information about the linkage of various races to physical anthropologists.

• Mitochondria have their own genome of about 16,500 bp that exists outside of the cell nucleus. Each contains 13 protein coding genes, 22 tRNAs and 2 rRNAs.
  
• they are present in large numbers in each cell, but the numbers vary from person to person
  
• they have a higher rate of substitution (mutations where one nucleotide is replaced with another) than nuclear DNA making it easier to resolve differences between closely related individuals.
  
• they are inherited only from the mother, which allows tracing of a direct genetic line
  
• they don't recombine. The process of recombination in nuclear DNA (except the Y chromosome) mixes sections of DNA from the mother and the father creating a garbled genetic history.
  

In Return of the Jedi, The Force is established as being genetically passed on. Obi-Wan remarks that:

"The Emperor knew, as I did, that if Anakin were to have any offspring, they would be a threat to him."

So while midi-chlorians with the vague and sketchy discussion really make very little sense, it is a better, more realistic basis if reviewed in the light of mtDNA which they appear to be based on. I do personally think, as annoyed with midi-chlorians as I am, there would have to be a physical component to The Force and the ability to tap into The Force.

One are not yet discussed is the explanation that they are symbiont's living within our cells. In The Phantom Menace, p. 241-242, this concept is explained:

"Midi-chlorians are microscopic life-forms that reside within the cells of all living things and communicate with the force."
"They live inside of me?" the boy asked.
"In your cells," Qui-gon paused. "We are symbionts with the midi-chlorians."
"Symbi-what?"
"Symbionts. Life-forms living together for mutual advantage. Without the midi-chlorians, life could not exist, and we would have no knowledge of the Force. Our midi-chlorians continually speak to us, Annie, telling us the will of the Force."
"They do?"
Qui-gon cocked one eyebrow. "When you learn to quiet your mind, you will hear them speaking to you."

As irritating as this high level comment that lacks a deeper, truer, understanding of life in general, the Human Body is entirely reliant upon a variety of symbiotic organisms living within us. All beings do. mtDNA is nothing more than a bacteria evolved to support life.

Unlike any other organelle, except for chloroplasts, mitochondria pretty much come only from other mitochondria, they are self-replicating. They contain their own DNA, which is circular as is true with bacteria, along with their own transcription and translational machinery. Mitochondrial ribosomes and transfer RNA molecules are still quite similar to those of bacteria, as are components of their membrane. It can be said that mtDNA are the rarest of life forms that can be "eaten" (phagocytized by larger cells and rather than digest the bacterial cells, the larger host cell stored it undamaged in a membranous vesicle within the cytoplasm) by another living life form and continue to exist.

Given all of this, mtDNA communicates, is essential to all life, self-replicates, is symbiotic, and varies in amounts from one living being to another, it is safe to say that Lucas took this fact of life, renamed it, poorly explained it at a higher level for audiences to 'understand', then again that is my one complaint with Star Wars is the lack of detail (probably accounted for by the fact it is Science Fantasy, not Fiction), and put forward the high level concept that merely aggravates and annoys. An injustice to the truths he derived it from. It is safe to say that at no point in time can any mtDNA ever be alluded to having caused a mysterious conception such as the one that supposedly produced Anakin Skywalker.