A long time ago, in a galaxy rather close to here …….
- The First Replicator
This is where it all started, and the first stop on our genetics timeline. It was THE biggest moment in genetics history. Now whether you believe in intelligent design, the randomness and spontaneity of nature, or that life was ceded from precursor molecules that came smacking into our planet on the back of a comet, at some point a molecule or partial molecule began to copy itself. A neat trick that led all the way up to us, or down to us, depending on your view of humanity.
There are lots of theories about what actually happened. Which came first the protein or DNA? Or did RNA act as a catalyst for both protein and DNA synthesis? Whatever the picture at some point a few random bits of biological and chemical material came together, into a form that copied itself, which eventually led to the mighty structure we know as the cell.
- A Burst of Life
One cell became two, two became four and so on until cells became tissues and eventually whole animals and species. It was an exciting time for the planet and for genetics. This hitherto barren rock was suddenly (well as sudden as a few billion years) full of life. Genes created millions of different life forms. There were mutations, speciation events, hybridizations, extinctions; species lived, species died, and all the while genes went quietly about their business. And that was pretty much the story for millions of years until another collection of genes came along ….. humans.
I’d like to think this was a big moment in genetics history. I’m pretty partial to being a human and genes created billions upon billions of us. Some of those humans started to become curious about life and how it all worked and slotted together. But it wasn’t until an Austrian monk began spending a little more time in his garden than was usual that the picture started to become a little clearer.
- Gregor Mendel
Gregor Johann Mendel was an Austrian monk with a family background in farming. He developed an insatiable curiosity about inheritance. From 1856 to 1863 he cultivated more than 20,000 pea plants in the monastery’s garden to study variation and heredity. Up until then a prevailing thought was that the next generation constituted a blend of characteristics from the previous one. Not just for peas but all life. It was Mendel who came up with the concept of hereditary units, now called genes. He showed that the inheritance of traits follow special laws. He also coined two terms we use today; dominant and recessive.
The work was seminal and truly groundbreaking so he published in 1866 and the whole wide world, ignored it. It lay in obscurity for about another 30 or so years, but it’s full significance wasn’t really understood until the 1920’s.
- DNA Identified
The scientific sleuth who identified it was Friedrich Miescher. He called it ‘nuclein,’ an acidic substance found in a cell’s nuclei. But its significance wasn’t fully realised for many years.
- The Structure of DNA
A monumental moment in the history of human genetics. It’s 1953 and more than half of America is glued to the television watching Lucy give birth on ‘I Love Lucy,’ Arthur Miller’s ‘Crucible’ opens on Broadway and two scientists, Francis Crick and James Watson, publish a paper on the structure of DNA. It showed how DNA replicates and how inherited information is coded on in it, and was one of the 20th century’s biggest scientific discoveries. It’s said that when the pair finished their work, they walked into a pub in Cambridge in England and announced that “we had cracked the secret of life.” Many of today’s advances in molecular biology spring from their work.
They incorporated into their paper the research of Maurice Wilkins and Rosalind Franklin. In 1962 Crick, Watson and Wilkins were awarded the Nobel Prize in Physiology or Medicine. But not Franklin. She had died in 1958 and the prize cannot be awarded posthumously.
- Huntington’s Disease
A genetic marker for Huntington’s disease is mapped to a chromosome in 1983. Based on this a genetic test for the condition was created. The marker told scientists the approximate location of the faulty gene that led to Huntington’s. The gene was eventually found nearly 10 years later.
- Gene Therapy
The world’s first gene therapy patient, a four year old girl, is treated by doctors in Bethesda, Maryland. She’s given genetically altered white blood cells to correct potentially fatal abnormalities in her immune system. Since then there have been hundreds of gene therapy trials, but it is a notoriously difficult procedure.
- First Cloned Mammal
Dolly the Sheep is arguably the most famous animal to have walked the planet. Lassie doesn’t even get a look-in. Born on the 5th July 1996, she was the first successful clone of a mammal. Her premature death 6 and a half years later was attributed by many as a fault of the cloning procedure. This is still speculative with many people still wanting to know what caused the death of Dolly the sheep? Since Dolly many more animal species have been cloned including cats and dogs.
- Human Genome Project
Probably the largest map in the world. A genome is an organism’s entire complement of genes and in 2003 The Human Genome Project published its completed draft of the thousands of genes in the human body. The entire base sequence of every gene had been elucidated. The work is pivotal in trying to understand what can go wrong when a gene malfunctions.
What comes next?
So there you have it, but this isn’t the end of the story. Although there have been many major advances during the last half century, the field of genetics is still in its infancy. And if I can stretch the analogy to breaking point, it’s just geting out of diapers. That’s not to underestimate the brilliant work of generations of scientists. There is so much we now know thanks to their huge brains, bu there is so much that we don’t.
The hope is that the potenital and many of the dreams will be realised, and no doubt the list of top 10 moments in genetics history will change over time.
The pace of change can be overwhelming at times, but society has to keep up to understand the new biological, medical and sometimes ethical avenues that are opened by each massive leap forward in our knowledge.