How Genetic Mutations Lead to Cancer: A Breakdown of BRCA1 and Cell Division

 Cancer can be compared to a car crash. Normally, your body regulates the speed at which cells divide, but sometimes, cancer is like cutting the brake lines, causing cells to divide too quickly. This rapid division leads to mutations that cause the cells to stray from their original function, form tumors, and potentially result in hospitalization. In essence, cancer occurs when the body loses control over the speed of cell division, leading to mutations that can create tumors and disrupt vital processes like digestion and respiration, sometimes even causing death.

Your body usually has genetic mechanisms to control cell division. One of these genes is BRCA1, which stands for Breast Cancer Susceptibility Gene 1. BRCA1 is part of a group of genes known as tumor suppressors, which help regulate how fast a cell divides. Cell division typically follows a structured process called the cell cycle, which includes checkpoints where proteins, like the ones produced by BRCA1, control the pace at which cells proceed. BRCA1 plays a crucial role in repairing DNA mutations. When DNA is damaged, BRCA1 prevents the cell from dividing until the mutation is fixed.

Each of your cells has two copies of the BRCA1 gene, one inherited from each parent. This redundancy is beneficial, as only one functioning BRCA1 gene is needed to regulate the cell cycle. However, while these copies perform similar functions, they can differ in effectiveness. There are hundreds of BRCA1 gene variations, or alleles, and some are more efficient in regulating and repairing DNA than others. Some people may be born with versions of BRCA1 that are more effective, while in some cases, mutations render BRCA1 ineffective.

When BRCA1 fails, cells with damaged DNA are allowed to divide unchecked. As they continue to divide, these cells can accumulate further mutations, potentially losing their original function and becoming less specialized. This increases the risk of these cells turning into cancer cells. While everyone has genes like BRCA1 that can lead to cancer, problems arise when these genes fail to perform their protective role. Having a mutated or ineffective version of BRCA1 is like driving with faulty brakes—it raises the risk of a crash, in this case, cancer.