Hidden deep inside the organisms of life and beyond the reach of human understanding, until recent times, are the very basic building blocks that transfers information from generation to generation. They are genes, the tiniest particles of existence that are responsible for who we are and what we look like. But they are more than that. They carry messages that can determine how long we live, what diseases we will suffer, what sex we will be, how we will function as an individual, and so on.
Without the knowledge of these things man set about making his own laws. He devised evil to explain bad characteristics, a devil’s influence to explain disease, and he harbored notions of ghouls and witches and things to blame for just about everything else.
As a medical student first off many years ago and then researching in my medical anthropology course at the Australian National University there was something about genes that grabbed my attention more than any of my other studies. They are markers that can determine the origin of a race, the migratory patterns of humans, and the secrets we might like to keep from the rest of the world. Genes determine us, who we are, how we speak, the shape of our nose, the color of our eyes and even our fertility and reproducing abilities.
Most people know of the double helix (pictured) and of the little knobs on either end of the cross bars but it is time to probe deeper and look inside to find out just how genes work.
The First Hint of the Structure of Chromosomes – The Double Helix:
As researchers worked to unravel how disease and characteristics were passed on a young lady, Rosalind Franklin, unraveled the crystallographic evidence of the structure of DNA when she attended Cambridge school of medical research. She worked in the same lab as Maurice Wilkins and Max Perutz. Her findings were recorded in a document that these two gentlemen then showed to two other scientists, Crick and Watson, without her consent or knowledge.
To backtrack a little “In 1944, Oswald Avery had shown that DNA was the “transforming principle,” the carrier of hereditary information, in pneumococcal bacteria” (cited Profiles in Science – National Library of Medicine). In 1951 Franklin began her research through X-rays of the structure of cells and gradually unearthed the double helix. The constant exposure to X-rays probably induced the ovarian cancer from which she died in 1958 without recognition for her part in the discovery that would change medicine forever.
The image is from Wikipedia open source and although it is dark it is nowhere near the faint outlines of genes that Franklin first saw under X-ray and she still had to explain what it meant. This took months of her time as she was not a biomolicular scientist as the others in her vicinity were. So there is a chance she may never have gotten any further, but things were taken out of her hands by the young enthusiastic, Crick and Watson, who were also working to unravel the genetic code.
Identifying the helix was the greatest triumph of her short life but once Crick and Watson got wind of it they quickly claimed it as their discovery and would later be awarded the Nobel Prize for physiological medicine. They published their findings in Nature in April, 1953
Amino Acids and Protein – Their role in genetic science:
Amino acid comprises nitrogen. hydrogen. oxygen and carbon linked together by electronic valency. That is the charged particles of their atoms are held together by magnetic force. A whole string of these molecules form what is termed protein. That is usually an elastic type substance in living cells. In fact, it can be termed the basis of life.
This is what cannot be manufactured in the laboratory by artificial means unless living cells are used to start with.
My first introduction to amino acid came through Ribonucleic acid or RNA. This is found in living cells. Another form of an amino acid is Deoxyribonucleic acid or DNA. This is the substance that contains the genetic instructions of all living things. It is the storage place of information that determines characteristics in new cells. One might call it a code, a blueprint or even a recipe for construction of protein and RNA. The segments that carry this information are genes. Along with them the rest of the DNA fulfills either a structural purpose or it serves to regulate the use of the genetic material
The DNA is organised into long strains called chromosomes. It is these that form the double helix that Franklin identified. But it was 20 years later before the true function of these cell particles was properly understood and the science of genetics was born.
The Effects of Recessive Genes – Prominent in Some Societies:
In isolated groups where marriage between cousins is normal there is often to be seen traits not normally found in the wider human population. These can include things like lack of pigmentation in eyes, skin and hair color, for example. We call these individuals albino.
Hemophilia is another trait related to recessive genes. It was a condition in many royal houses where cousins married each other to retain power and control. The Russian Royal Family suffered from this condition which may have come from Queen Victoria who was a carrier. She passed the condition to two of her daughters, one of whom was married to the Tsar of Russia, and one of her sons. . It means that the blood lacks the ability to clot due to the missing Factor VIII Alexi inherited from his mother.
Huntington’s Disease is another recessive genetic trait. It usually manifests itself after the age of 30 and causes a progressive destruction of brain cells. If present in a parent 50% of the offspring will inherit the disease unless there are other factors involved.
One of the diseases I studied and will talk about in another article is Sickle cell anemia. This can be fatal at any age and death may occur as a result of a lack of oxygen and the sickening of blood cells. This can be brought on by sudden shock, elevation into thin air, and other things. There is usually no warning beforehand.
This is only a brief look at some of the recessive factors and their effects. But there are many others that can be studied by the enthusiast.