Genomics
What is Genomics?
Genomics is the study of the genes in our DNA, their functions and their influence on the growth, development and working of the body.
Genetic testing – sometimes called genomic testing – finds changes in genes that can cause health problems. It's mainly used to diagnose rare and inherited health conditions and some cancers.
You may be offered a genetic test because if your doctor:
- thinks you might have a health condition caused by a change to 1 or more of your genes
- someone in your family has a health condition that's caused by changes to genes
- some of your close relatives have had a particular type of cancer that could be inherited
- you or your partner have a health condition that could be passed on to your children
You will generally only be referred if you have a suspected genetic health condition or if you have a particular type of cancer.
Genetic testing is free on the NHS if you are referred for it by a hospital specialist.
Genomics vs Genetics: What’s the difference?
Genetics is the study of individual genes and how they are inherited.
Genomics looks at all of a person’s DNA, including genes (genome); studying diversity, function and interaction within the genome and the environment. There are over 20,000 genes in the human genome, arranged across 23 pairs of chromosomes.
Source: Genomics Fun Facts: Genetic Differences - Genomics Education Programme
Why it matters: Understanding this distinction helps inform patient care decisions, especially in areas like rare diseases, cancer, and personalised treatment.
Patterns of inheritance: What you need to know
Autosomal Dominant Disorders:
Autosomal Recessive Disorders:
X-linked Conditions:
Epigenetics: Genes respond to the environment
Epigenetics refers to changes in gene expression without altering the DNA sequence itself. Factors like stress, nutrition, and pollution can "switch on" or silence certain genes—offering new insight into disease prevention and personalised care.
