The concepts of heredity and immunity are becoming more and more essential aspects of biology. Heredity is the study of genes and generational traits. The wealth of knowledge we have on combating diseases grows each day. However, a connection between these two vastly different fields has only recently been made – a connection that could potentially revolutionise the way we approach modern medicine and science.
Where is the Connection?
Recently, scientists participated in an excursion designed to extract genetic information from those buried in London’s ‘plague pits’ – a location designed solely to bury those who had both survived and succumbed to the Black Death. This plague rampaged through the world, killing approximately 50% of Europe’s population – but the DNA samples extracted from those who survived this deadly disease uncovered amazing information. There was a specific variation of the gene known as ERAP2 present within the survivors that gave them some form of resistance to the disease, severely decreasing the chances of contracting the disease.
Relevance
The Black Death is luckily not a prominent threat today. How is the discovery of the ERAP2 variant relevant to modern medicine? Scientists traced the descendants of survivors of the Black Death, and encountered something revolutionary – the ERAP2 variation present in the descendants of those survivors decreases the risk of them contracting COVID-19. When this information was eventually traced back to the descendants, they hadn’t had COVID, or had mild symptoms of a disease that was killing others. This discovery did wonders for understanding inheritance and infection, but it came with a cost.
What is the Downside?
While the ERAP2 variant gave certain people a very obvious advantage at the time of a global pandemic, it came with a big disadvantage – patients had an increased risk of developing autoimmune diseases. The ERAP2 variant speeds up an inflammatory process that occurs when trying to eliminate pathogens – this means that over time, their immune systems get stronger, unlike the rest of the population.
However, as an immune system continues to build up strength, it can often reach a limit after which it can begin recognising normal microorganisms as a threat to the body, meaning that the immune system can begin to work against the rest of the body, attacking it violently – this is the main cause of autoimmune diseases, and this can have a drastic effect on a person’s life.
So overall, genetics and disease do go hand in hand, but is that necessarily a good thing? That is the question scientists will have to consider when steering the world towards a more scientifically advanced future.
SOURCES
https://www.npr.org/sections/goatsandsoda/2022/10/19/1129965424/how-black-death-survivors-gave-their-descendants-an-edge-during-pandemics
https://www.bristol.ac.uk/news/2023/march/black-death-study.html
