Gene

A gene is a small section of DNA that provides the instructions for making a specific protein. These proteins help the body grow, develop, and carry out important functions. Genes are found inside almost every cell in the body and are passed down from parents to children. Each person has approximately 20,000 genes, and each gene has a specific function. For example, some genes help build muscle or bone, while others help protect cells from developing into cancerous cells.

What is DNA?

DNA (deoxyribonucleic acid) is the genetic material that makes up our genes. It contains all the information necessary to build and maintain the body. You can think of DNA as the instruction manual for how the body works. Genes are like individual chapters in that manual, each with its own set of instructions.

Where are genes found?

Genes are located on structures called chromosomes, which are found in the center (nucleus) of each cell. Humans have 23 pairs of chromosomes (46 in total), and each pair contains copies of the same genes—one from each parent.

What happens when a gene is changed?

A change or error in a gene is referred to as a mutation or variant. Some changes have no effect, while others can cause a gene to malfunction. If a gene that typically prevents cancer is damaged, for example, it may increase the risk of developing cancer.

Why are genes important in a pathology report?

Some pathology reports mention genes because changes in specific genes can affect a person’s diagnosis, treatment, or risk of developing future diseases. For example, inherited changes in the BRCA1 or BRCA2 genes can increase the risk of breast and ovarian cancer. Doctors may recommend genetic testing to identify changes in these or other genes, especially if there is a family history of cancer or other hereditary conditions.

How do doctors test for gene mutations?

Gene mutations are most often detected using a method called next-generation sequencing (NGS). This test examines the DNA closely to identify any changes in specific genes. A sample of blood, saliva, or tissue may be used for analysis. The results can help doctors choose the most effective treatment, recommend cancer screening, or take preventive measures.

Questions to ask your doctor

• Do I need genetic testing to check for gene mutations?
• Could the condition I have be related to an inherited gene mutation?
• What do my test results say about the genes in my tumor?
• Should my family members also be tested?