History: The Story of Genetics

One of the first records of inheritance is shown on a 6,000-year-old Babylonian tablet, confirming that humans have recognised that traits are passed from parents to their children, and that plants and livestock can be bred for beneficial characteristics, for thousands of years. Although the existence of inheritance has been recognised for millennia, the mechanism has only been discovered in the last 200 years, making the history of genetics a relatively short, but fascinating one.

Inheritance was first studied scientifically in the mid-19th century, alongside the theory of evolution. Charles Darwin began to theorise that organisms adapt overtime to their environment. Through survival of the fittest, those organisms with favourable characteristics are more likely to survive and reproduce to pass on the same favourable characteristics to their offspring.  

A few years later, Gregor Mendel, a German monk, began experimenting on pea plants, and inadvertently discovered how these traits are passed from one generation to the next. Mendel crossed yellow pea plants with green pea plants. The resulting pea plants were all yellow. Mendel then decided to cross this first generation of yellow pea plants together. Interestingly, of the second generation of pea plants, ¾ of them were yellow and ¼ of them were green. Mendel theorised that the green colour was masked by the presence of the yellow colour, meaning that the colour yellow in the pea plants was dominant over the recessive colour green. These findings were ground-breaking and were instrumental in the understanding of modern genetics, and because of this, Mendel has been hailed as the “Father of genetics”.

Although Mendel’s findings showed the process of inheritance and the law of dominance, it was still not known exactly how these characteristics are passed on. However, the years after Mendel’s discovery saw rapid advancement by other scientists in the understanding of the nature and function of genes. In 1869 the nucleus was isolated in white blood cells, in 1871 the nucleus was discovered as the home for genetic material, and in 1944 DNA was proven to be the molecule responsible for inheritance. These findings were, and still are, revolutionary; for example, with the discovery of DNA, it was then possible to understand how genes are responsible for every function in the body, what happens when genes mutate, and how these changes can be fixed.

In 1977, Frederick Sanger was able to sequence the entire genome (all the genetic information in an organism) of a virus. Then just 30 years ago, in 1990, scientists began the process of sequencing the human genome, in an international scientific research project called The Human Genome Project, which attempted to create a blueprint for human genetics. This was completed in 2003, and has been invaluable in the medical field; because of this incredible work, scientists can compare an individual’s genes to the sequenced human genome, to identify if there are any differences in a patient’s genes and whether differences are associated with a patient’s illness, also influencing the type of medication prescribed.

Ultimately, the field of genetics has seen remarkable advancements since Mendel’s discovery in the 1860s. However, compared to the field of mathematics, which has been studied since around 600 B.C, the field of genetics is still a very young science. This means that there are still many aspects of genetics that we don’t understand. It is therefore very exciting to be living in a time when new discoveries are found every day, and potentially, for one of these discoveries to be a momentous breakthrough, equal to that of Mendel. In the story of genetics, we're just in the first chapter.

 

References

https://www.bioexplorer.net/history_of_biology/genetics/

https://www.britannica.com/science/genetics

https://www.news-medical.net/life-sciences/History-of-Genetics.aspx

https://scienceofhealthy.com/history-genetics/

https://www.newscientist.com/article/dn9966-timeline-genetics/

 

Disclaimer

The information in this blog is for information and entertainment purposes only. I am not a medical professional, so I have never and will never give medical advice in this blog. You should always speak to a healthcare professional about your unique health needs. My opinions are entirely my own and do not reflect the organisations or people I work for. I only discuss published literature in this blog which are referenced with links.

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