The Gentic Roadmap of C. elegens

 

In the beginning there was common, plain, ordinary ammonia which is a nitrogen atom with three hydrogen atoms attached to it. It is commonly found throughout nature as well as on other planets in  our solar system.

These days we manufacture some 235 million tonnes (about 500 million tons) of the stuff which is used primarily to produce fertilizer which without we would be unable to feed only half the 8 billion people on earth. When mixed with water, ammonia is a common ingredient in household cleaners that breaks down grease and grime.

But, even more importantly, is essential any life at all. When when one of the hydrogen atoms in ammonia is replaced by a carboxylic acid radical, an amino acid results. And while many amino acids are possible, some 20 of them are essential to life:

• Alanine
• Arginine
• Asparagine
• Aspartic Acid
• Cysteine 
• Glutamic acid
• Glutamine 
• Glycine
• Histidine
• Isoleucine
• Leucine
• Lysine
• Methionine
• Phenylalanine
• Proline
• Serine 
• Threonine
• Tryptophan 
• Tyrosine 
• Valine
• Selenocysteine
• Pyrrolysine

A few of them, such as tryptophan, are commonly known . Turkey meat has a relatively large amount of tryptophan in it and it prompts that drowsiness when you overeat Thanksgiving turkey. Histidine (which degrades to histamin)  prompts you to break out in hives and to take an antihistamine to combat it. Most all play some role in the regulate the chemical processes (homeostasis) that take place internally so as to maintain health and functioning, regardless of outside conditions. Amino acids such as tryptophan, tyrosine, histidine, and arginine are used by the organism  for the synthesis of various neurotransmitters and neuromodulators

But, even more importantly, these 20 amino acids are jointed together to create an enormous number of possible protein. And the numbers, kinds and order of the amino acids in the chain of them that form a protein coded -- predetermined -- by the genes in its DNA of each species of animal. It is these proteins produced in our living cells that determine what we are, who we are and how we behave. It is, in the end, what determines the chemistry of life itself.

Human DNA has 20,000 to 25,000 protein-coding genes some of which coded for more than one protein. But the exact number of different proteins remain  uncounted above about 18,000.

C. elegens has a similar number of protein-coding genes, for which about 35% are shared with us humans. Many thousands of proteins have been identified in C. elegens.

Any defects in the protein-coding genes can results in behaviors that are abnormal for the organism. These we call genetic disorders. Such disorders include autism, attention deficit hyperactivity disorder (ADHD), bipolar disorder, major depression and schizophrenia. 

Similarly defects in certain genes, especially the MAOA gene have been found to be antisocial/criminal behavior in  humans when couple with social environment factors. The C. elegans genome encodes several proteins with homology to MAOA

And so it is that both C. elegens and humans are both collections of atoms and molecules controlled by proteins designated by the genes in our DNA that enable us to live and live to reproduce and to do so while affecting  our behavior in response to the outer world that surrounds us.