Genetics of cancer

Cancer is one of the serious problems in today’s world. Even the researchers, doctors and scientist are unable to find the exact cause of cancer but the unnecessary change in the gene due to mutation or its improper functioning is the basic reason for the cancer. So before going deep into the topic of cancers and talking about the genes involved, it is important to first know that what are genes and how they functions in our body.

Genes are the main elements of the cell that are made of DNA fragment. These are the main point that determines how the cell function and works, this is done when these genes codes for proteins those are necessary for the cell to provide all the necessary information. Therefore, correct coding is very much necessary for proper functioning of the cell and incase the coding gets wrong due to mutation, it certainly leads to cancer.

It would be wrong to say that any mutation will result in cancer because mutation generally happens in the body but are usually corrected by the system. Further, Mutation can be divided into two types; like germ line mutation and acquired mutation. Acquired means those mutation that arise due to changes in the genes at later stages like UV rays, chemicals etc whereas germ line mutation means the mutation that are inherited form the parents and these accounts for very less percentage of cancer.

The development of cancer is not preceded in a single step; rather it involves number of steps that changes the normal cell into malignant cell due to some alterations. The increase in capacity of the cell for proliferation, survival, invasion and metastasis finally leads to cancer.

Now coming to the main portion of the topic, the genes that cause cancer can be divided into various types; the first one is tumor suppressor gene and the other is oncogenes.

Tumor suppressor gene: Tumor suppressor genes are important genes that look different process of the cell. It looks upon any mistakes that have occurred in the DNA and repairs it; it carries the process of cell apoptosis I.e. death of the cell. The most important thing about these genes is that it slows down cell division so that cell divides in the normal way. Therefore, it can be said that these are protective genes. Now we can figure out that mutation in this gene can lead to cancer because once these genes gets mutated, cell start to divide in an uncontrolled way thus resulting in tumor and hence finally to cancer. The examples of such genes are P53 and RBI etc.

Oncogenes: Before going onto oncogene, it is important to learn about proto- oncogene. Thus, a proto- oncogene is that gene that helps cell to grow and progress. But when this gene anyhow mutates; then it becomes oncogenes that is dangerous for the cell making them grow in uncontrolled manner thus turning into bad gene. These genes when turns on starts the proliferation of cell thus causing cancer. Example of these genes includes Myc gene, sis gene, Src gene etc.

Beside these two types of gene, there is one more type of gene that can result in development of cancer. The gene is thus named as DNA repair gene. This DNA repair gene helps to correct any mistakes in the DNA and thus help in proper functioning of the cell and the body. Hence, any problem in this gene can led to mutation that in turn can be pathway towards cancer. Other than this, some of the genes that cause cancers in human are hepatitis B viruses, hepatitis C viruses, papillomaviruses, herpesviruses and many more.

We cannot protect ourselves from getting cancer but we can adopt good habits and healthy living environment that keeps our system healthy and well functional.