Many people wonder if Alzheimer’s disease runs in their family. Is it in your genes? This question isn’t easy to answer. Researchers have identified several genetic variants that are associated with Alzheimer’s and may increase or decrease a person’s risk of developing the disease. What does that mean? Let’s first learn about the role of genes.
What are genes?
Human cells contain the instructions needed for a cell to do its job. These instructions are made up of DNA, which is packed tightly into structures called chromosomes. Each chromosome has thousands of segments called genes.
Genes are passed down from a person’s biological parents. They carry information that defines traits such as eye color and height. Genes also play a role in keeping the body’s cells healthy.
Variations in genes — even small changes to a gene — can affect the likelihood of a person developing a disease such as Alzheimer’s.
Do changes in genes cause diseases?
Permanent changes in one or more specific genes are called genetic variants. Some of these variants are quite common in the human population. While most genetic variants don’t cause diseases, some do. In some cases, a person inherits a genetic variant that will almost certainly lead to that individual developing a disease. Sickle cell anemia, cystic fibrosis, and some cases of early-onset Alzheimer’s are examples of inherited genetic disorders. However, other variants may simply increase, or even decrease, a person’s risk of developing that disease. Identifying genetic variants and their effects can help researchers uncover the most effective ways to treat or prevent diseases in an individual.
Additionally, factors such as exercise, diet, chemicals, or smoking can have positive or negative effects by changing the way certain genes work. In the field of epigenetics, researchers are studying how such factors can alter a cell’s DNA in ways that affect gene activity.
Genetic research is a component of precision medicine, an emerging approach that considers individual variability in genes, environment, and lifestyle. Precision medicine will enable researchers and doctors to predict more accurately which treatment and prevention strategies will work in particular groups of people.
