How Genetics Shapes Your Life

What is genetics? It is all information about us, humans and also information about animals and plants. Why do some people have blue eyes and others have green or brown? And the same with hair colours, blond, brown, black. So many variations. For animals it is even more.

Genetics is responsible for our look

Genetics is also our body type, muscular, slim, tall, athletic, curvy. Some people have a lot of energy and others are weak and tired. The information about how we look, how we behave and susceptibility to certain illnesses is all written in our DNA. Every person’s DNA is unique, there are different combinations of genes that determine who we are. This genetic information is transmitted in DNA from our parents. It creates not only differences in physical appearance but also in personality. The modern study of genetics is a quite recent study. The foundations of modern genetics were laid by Gregor Mendel, whose pioneering work with pea plants in the mid-19th century established the fundamental principles of inheritance and variation that are still studied today. The 20th century came with a breakout when the DNA structure was discovered by Watson and Crick in 1953. Their discovery was based on the work of Rosalind Franklin. She was the first person who obtained an image of DNA by X-ray crystallography. It showed the general shape and size of this molecule. Thanks to advances in genetic research, we are now able to unlock the secrets of our DNA and gain a better understanding of how genetics shapes our lives.

Genetic testing

When genetics became more advanced, people developed different methods to check what is written in our DNA. We can identify mutations in our genes that may increase risk of  developing certain diseases. Quite famous genes called BRCA1 and BRCA2 are responsible for increased chances of having breast and ovarian cancer. People who have in their family history these cancers should do a genetic test to determine if they carry these mutations. This information can help to reduce the risk of developing cancer by having more frequent screenings or even preventive surgeries.

Personalised medications based on your genetics

Due to the fact that we all slightly differ from each other it is important to adjust certain medications to each patient. It is particularly important in the treatment of complex diseases like cancer. Differences in our DNA make our responses to medications different. Taking these genetic differences into account, doctors can create personalised treatment that is more effective. Pharmacogenomics is a field of studies that checks responses to medications based on a patient’s genes. It can help to identify genetic mutations in the patient and these mutations can have an effect on metabolism of drugs. Certain patients can metabolise certain drugs more slowly or more quickly. This difference can create side effects or the treatment could be ineffective. 

Genetics is also personality

Beside risks of different diseases, genetics also plays a significant role in our personality and behaviour. It is already known that certain genes are responsible for particular character traits such as extraversion, neuroticism, creativity, intelligence, aggression, empathy or risk-taking behaviour. Genetics is just one factor in shaping personality and behaviour. There are also environmental factors, such as upbringing and life experiences. They also have a big influence on our character. It was observed in identical twins that their personalities can differ when they were separated and grew up in different environments.

Environmental factors can change our genes

The study of epigenetics examines how environmental factors can alter gene expression, leading to changes in our physical and behavioural traits. Some external factors can trigger certain genes to become active or others not to be active and it is not based on information written in our DNA. What can cause certain changes is diet, stress or exercise. It can trigger some diseases to be developed. Even a mother’s diet can have an influence on the gene expression of the baby. A study published in Nature describes that a mother’s diet during pregnancy can influence her child’s risk of developing obesity. The child can also develop metabolic disorders because expression of certain genes will be affected.

Other examples how genetics can shape our lives

• Athletic ability: Certain genes are associated with endurance, muscle strength, and other physical attributes that can influence athletic ability.
• Taste preferences: Our genes are responsible for how we perceive certain flavours, such as bitterness or sweetness. This influences our food preferences.
• Ageing: Some genes are associated with the ageing process, such as the telomerase gene. It plays an important role in cell division and may affect how quickly we age.
• Intelligence: It can be influenced by many factors, however certain genes may play a role in our intelligence.
• Less stress: Even meditation and yoga practice can change our genes. Read more about how yoga can change your genes

References:

Brittannica – Rosalin Franklin

Brittanica – Francis Crick

Desai, M., Jellyman, J. & Ross, M. Epigenomics, gestational programming and risk of metabolic syndrome. Int J Obes 39, 633–641 (2015)

National Institute of General Medical Sciences – Pharmacogenomics