How Do Mutations Occur Naturally?

A mutation is a change that occurs in a DNA sequence. It may be due to a mistake during the replication or due to environmental factors, such as exposure to UV radiation or smoking. 

Genetic variations occur because of mutations. Some mutations can be inherited by offspring.

Mutations can be harmful or beneficial; sometimes, they do not have any effect. Certain genetic mutations can cause cancer.

There are various types of mutations. Based on whether they can be passed on to offspring, mutations are divided into two types:

1. Germline mutations: These mutations occur in the egg and sperm and can be passed on to offspring. These kinds of mutations affect the genetic makeup of a child.
2. Somatic mutations: These occur in body cells and cannot be passed from parents to offspring.

Mutations also differ in how the genetic material is altered. Mutations can alter the structure of a chromosome or just one nucleotide.

Various reasons can cause mutations. Mutations are genetic errors that occur during the replication of DNA. Sometimes, mutations can be caused by environmental factors known as mutagens.

Environmental factors that cause mutations include:

• Radiations, such as UV radiation and X-rays
• Chemical mutagens, which include nitrate and nitrite preservatives, benzoyl peroxide, and cigarette smoke
• Infectious agents such as Helicobacter pylori and human papillomavirus

Examples of conditions caused by genetic mutations include:

• Marfan syndrome
• Sickle cell disease
• Fragile X syndrome
• Color blindness
• Thrombocytopenia
• Webbed toes
• Leber hereditary optic neuropathy (sudden loss of vision)
• Alpha-1-antitrypsin deficiency
• Alzheimer's disease
• Developmental delays
• Cystic fibrosis
• Some types of cancer

Genetic mutations that occur naturally take place during cell division.

• During cell division, the cells divide and write the body's instructions by copying the original structure of DNA.
• There is a high chance of mutation during the cell division process because the cells might substitute, add, or remove a part while copying the original structure of DNA, resulting in errors in DNA replication.
• These errors that occur during DNA replication result in abnormal functioning of the cells.

Many mutations do not cause any effect, whereas a few of them are beneficial and improve fitness, such as mutations that confer antibiotic resistance in bacteria.

Some genetic mutations are harmful and can affect the overall health of an individual. They can lead to dangerous conditions, such as cancer and other genetic disorders, which include:

• Trisomy 13
• Trisomy 18
• Turner syndrome
• Fragile X syndrome
• Triple X syndrome
• Klinefelter syndrome
• Down syndrome (trisomy 21)

Genetic mutations can sometimes prevent one or more proteins from functioning normally, which may result in a few symptoms. The symptoms of a genetic mutation depend on the type of gene that is mutated. Genetic mutations cause various diseases and conditions.

The following are the signs and symptoms triggered by genetic mutations:

• Physical changes, such as facial abnormalities, cleft lip and cleft palate, short stature, webbed fingers, and toes
• Cognitive problems, such as intellectual disabilities and developmental delays
• Vision and hearing loss
• Breathing problems
• High risk of cancer

Some genetic mutations can occur randomly and cannot be prevented from occurring. However, some mutations that are caused by environmental factors, such as mutagens, can be prevented in the following ways:

• Avoid smoking.
• Apply sunblock while going out.
• Avoid chemical exposure to certain carcinogens and UV radiation.
• Eat healthy and balanced foods, and do not eat processed foods.