What are mutations in genetics? Are mutations caused by genetics? Are they all dangerous? We answer these and other questions in the article.

What are genetic mutations?

A genetic mutation is any change in the nucleotide DNA sequence. What is the genetic mutation: normal or pathological? Mutations occur throughout our lives. We can say that it is a normal phenomenon that happens during different processes, for example, when DNA is copied during cell division (spontaneous mutations). Mutations occur under the influence of unfavorable environmental factors also, e.g. chemicals, ionizing radiation or infection with viruses (induced mutations). They also can be passed from parents to offspring through germ line cells (sperm or egg). 

Mutations can be classified into several types based on their nature and impact. They can be categorized into gene mutation, chromosome mutation and genome mutation. Gene mutations occur within a single gene, chromosomal mutations occur within a single chromosome (larger structural changes, including duplications, deletions, or translocations), and genomic mutations involve a change in the total number of chromosomes. These changes can alter how genes function, potentially leading to diseases, beneficial adaptations, or neutral effects.  

By understanding mutations, researchers can better analyze genetic diseases, improve crop resilience, and explore evolutionary processes.

Somatic and germline mutation: what is the difference?

Somatic mutation is a change in the genetic material of somatic cells (any cell in an organism other than the germ cells). They are present only in ‘damaged’ tissues, occur during life and are not inherited.

Germ line mutations are inborn DNA changes. They are present in all cells of the body and are caused by changes in the genetic material of the germ cells of the parents. These changes are then passed on to the children. 

To determine somatic mutations, DNA from damaged tissue is examined, usually biopsy material. To determine germinal mutations, virtually any tissue of the body is examined, usually blood (nucleus-containing cells – lymphocytes) or buccal (cheek) epithelium. 

What does mutation lead to?

We answered the question, What is a genetic mutation, But it is also important to understand what they can lead to. 

Mutations can cause genetic disorders. But not all genetic mutations are dangerous. They are also a driving force of evolution and diversity, showing their complex role in biology and health. Changes in genes entail changes in the characteristics of an organism, and as a result it can become either more or less adapted to survive. These safe differences in DNA are often referred to by another term: genetic variants. For example, scientists know that people with a certain GPR75 gene variant have a 54% reduced risk of obesity. Gene mutations can also provide other benefits to humans: for example, a mutated EPOR gene gave Finnish skier and three-time Olympic champion Eero Mäntyranta a high sensitivity to erythropoietin, a hormone that helps our cells maintain optimal oxygen levels and remove carbon dioxide. This changed both the volume of red blood cells in the athlete’s blood and the amount of oxygen these cells are able to carry. As a result, Mäntyranta gained super endurance – his body could easily cope with the increased oxygen demand during exercise.

But when mutations interfere with critical cell functions, they can result in common genetic disorders, which are often inherited or occur spontaneously. A strong family history of certain diseases may indicate the presence of inherited mutations. For example, mutations in the BRCA1 gene are linked to breast cancer; CFTR mutations cause cystic fibrosis. And mutations in the HBB gene lead to sickle cell anemia, a disorder in the structure of the hemoglobin protein, which carries oxygen from the lungs to the organs. It’s most common genetic disease in individuals of African or Mediterranean descent. Huntington’s chorea, a severe disease of the nervous system, develops due to a mutation in the HTT gene. A genetic test is needed to diagnose these diseases. 

However, not always a genetic disease is associated with a mutation in a single gene. For example, Down syndrome is caused by a change in the number of chromosomes – the cells of patients with this disease have 47 chromosomes instead of the usual 46. Such mutations affect the organism more seriously, leading to developmental delays and characteristic physical traits. 

A number of diseases, such as cancer, diabetes, and autism spectrum disorders, arise from a combination of factors. Patients may have a genetic predisposition, but external factors also play a significant role – improper lifestyle, unfavorable environment. Genetic testing can identify specific mutations linked to familial patterns of disease. The risks identified will allow for targeted prevention through lifestyle and dietary changes. 

By asking, “What is genetic mutation?”, we open the door to understanding the molecular basis of life, its diversity, and its vulnerabilities. Understanding genetic mutations helps researchers develop treatments for diseases, design gene therapies, and study evolutionary processes. Tools like CRISPR-Cas9 have revolutionized the ability to edit mutations, offering hope for curing inherited disorders.