Genomics is the study of a person’s DNA, their genes, how they are expressed and how they interact to influence the development and working of the body. Genomics makes a difference to each and every one of us. Your genes affect many things about you, including how you look and how your body works.

There are many ways in which your genetics can have an impact on your health, in both the long and short term. These include:

  • Inherited conditions: many health conditions can be passed down through families. Some of these conditions can cause direct health issues, such as cystic fibrosis, whilst some inherited conditions cause an increased likelihood of developing other illnesses, such as Lynch Syndrome increasing the chance of getting certain types of cancer.
  • Medication response: sometimes, people respond differently to drugs depending on their DNA. We can utilise genetic and genomic information to tailor pharmaceutical treatment; for example, around 5% of people will have a severe hypersensitivity reaction to the HIV/AIDS drug Abacavir. Testing is required before Abacavir is prescribed in the UK which has reduced the prevalence of this reaction.
  • Recovery from illness: emerging evidence suggests people recover from certain illnesses at different rates and with varying levels of success based on their genes. For example, ongoing research suggests that environmental and medical factors do not provide sufficient cause for the difference in recovery rates from COVID-19 for certain groups and research is aiming to establish if genetics is involved in this.
  • Genomics is the study of an organism’s complete set of genetic information, or the genome: the complete genetic information of an organism. The Genome includes both genes, which are coding (responsible for making proteins) and non-coding DNA.
  • Genetics is the study of heredity and of the function and composition of single genes. A gene is a specific sequence of DNA that codes for a functional molecule.

A genetic test identifies gene changes that can cause health issues. Genetic/genomic tests are generally used to diagnose inherited health conditions, including rare diseases and some cancers. A doctor needs to refer you for genetic testing on the NHS, and you’ll usually only be offered it if clinicians suspect you have a genetic condition, or if you have a particular type of cancer. There are also large-scale projects which are testing patients without suspected health conditions, such as the Generation Study which is aiming to sequence the genomes of 100,000 newborn babies to identify if they have one of over 200 actionable conditions.

Your doctor will refer you for genetic testing if they believe it is necessary. Upon attending clinic to have your sample taken, you will have either your blood or saliva taken. If it’s a genetic test related to a cancer, the test will be done on a sample of the tumour that was taken as part of the treatment. The sample is sent to a laboratory to be analysed. You’ll be told when to expect your test results – this could be weeks or months, and you might need to attend again for further testing. When you get your results, you’ll be told what the impact could be, and you may be referred to a genetic counsellor who will discuss the results and their impacts on you and your family.