This glossary describes terms related to genomics that are frequently used on this website. It aims to provide basic knowledge to enable a clear and relevant discussion among lay people. Words marked with an * are explained themselves in this glossary.
| Terms | Descriptions |
|---|---|
| Carrier status | A carrier is someone who has one copy of a gene with a variant that can cause disease. Usually, carriers themselves do not have any symptoms of the disease, but they can pass the variant to their children. If both parents are carriers of the same variant, there is a chance that their child may inherit both altered copies and develop the condition. |
| Carrier screening | A type of genetic test that checks whether a person carries a variant that could be passed on to their children and cause a genetic condition. |
| Cascade screening | Testing family members of someone with a genetic condition to see whether they also carry the same hereditary variant. This helps identify relatives who may be at risk. |
| Complex disease | A health condition caused by a combination of genetic factors, lifestyle behaviours, and environmental influences. Examples include diabetes, heart disease, and many types of cancer. |
| Congenital disease | A condition present from birth that can be caused by genetic factors, problems during pregnancy, or a combination of both. |
| Direct-to-consumer test | A type of genetic test that people can order themselves, usually online, without medical assistance. The results may give information about ancestry, traits, or health risks. |
| DNA | The hereditary material that is in every cell of our body and contains our genes. It strongly influences how our body looks, develops, and functions. |
| Exome | A small part of the genome (about 1.5%) composed of exons, which are the sections of genes containing instructions to make proteins. Whole-exome sequencing is sometimes preferred because it is cheaper and requires less data analysis. |
| Gene | A section of DNA that contains instructions for making specific proteins that help the body work. Our genes contain the information needed to specify our biological and physical characteristics. |
| Genome | All the genetic material (DNA) in our body. It includes all our genes. |
| Genomics | The study of the entire genome, including how all genes interact with each other and with the environment to affect health and disease. |
| Genotype | An individual’s collection of genes. Humans have a lot of DNA in common, but some genes vary from individual to individual, making each genotype unique. |
| Mutation | A permanent change in the DNA sequence of a gene. Some mutations have no effect, while others can cause disease or influence how the body works. |
| PRS (Polygenic Risk Score) | A score that calculates a person’s probability of developing a disease based on the combined effect of many small genetic variations across the genome. |
| Personalised medicine | An approach to healthcare that tailors prevention, diagnosis, and treatment to each person’s genes, environment, and lifestyle. |
| Pharmacogenomics | The study of how a person’s genes affect their response to medicines, helping doctors choose the safest and most effective drugs and doses. |
| Phenotype | Observable characteristics such as height, skin colour, or blood type. Phenotype is influenced by both genes and environmental factors like nutrition and lifestyle. |
| Rare disease | A condition affecting a small proportion of the population. Most rare diseases have a genetic cause. |
| Sequencing | Determining the exact order of the building blocks (A, T, C, G) that make up a DNA fragment. |
| Variant | A variation in the DNA sequence compared to what is common in the population. Some variants have no effect, while others may increase or reduce disease risk. |
| VUS (Variant of Uncertain Significance) | A DNA variant whose effect on health remains unclear. More research is often needed to understand its impact. |
| Whole Genome Sequencing (WGS) | A laboratory method that reads the complete DNA sequence of a person’s genome to identify variants that may affect health or disease. |