Introduction
A mutation is a change in the DNA sequence caused by errors in DNA copying during replication contact with ionizing radiation, mutagens, or viral infection. Cancer is a good example of a germline mutation that may be handed down from parents to offspring (Karamysheva et al., 2020). Somatic mutations arise in body cells; therefore, they are not passed down to offspring, such as human genetic illness that is called cystic fibrosis.
Main body
The amount and sequence of the 20 amino acids produced by cells determine the function of a protein. DNA comprises four nitrogenous bases: adenine, cytosine, guanine, and thymine, and each one has its codon that encodes the amino acid. Changes in DNA can affect amino acid sequence, reducing or inactivating protein function, and the gene’s regulatory region’s DNA sequence can affect the timing and availability of its protein, causing cellular dysfunction (Karamysheva et al., 2020). Silent mutation passes unnoticed because of their lack of phenotypic mutations.
Base pair substitutions can result in mutations, for example, point mutations. Many mutations alter the function of the encoded protein by putting an incorrect amino acid in the appropriate place (Karamysheva et al., 2020). The hemoglobin component essential for carrying oxygen in red blood cells is faulty due to mutations in the beta-globin gene (HBB). Hemoglobin S is a protein with one amino acid altered. This facilitates the development of long, brittle mutant protein fibers inside red blood cells. These fibers damage red blood cells, leading them to expand into sickles leading to sickle cell disease.
Chromosomal mutations impact many genes and change their structure, function, and inheritance. DNA breaks and incorrect rejoining may cause this type of mutation. Among the results are deletion, duplication, inversion, and translocation. Aneuploidy is a genetic disease characterized by chromosomal loss or gain (Karamysheva et al., 2020). Due to an extra chromosome 21, persons with Down syndrome have three copies of the genes rather than two, causing aneuploidy. Chromosome sets can be added or deleted on their whole, resulting in chromosomal mutations. Polyploidy can occur when more than two chromosomal groups are present.
Conclusion
In conclusion, mutations are random alterations, mostly harmful, but others may be advantageous under specific situations. Mutations can result in diseases in the human body due to the changes in the DNA sequence; this can occur in point, chromosomal, somatic, and germline mutations (Karamysheva et al., 2020). The mutation is the primary source of genetic diversity used in natural selection, both in plants and animals.
Reference
Karamysheva, T. V., Gayner, T. A., Muzyka, V. V., Orishchenko, K. E., & Rubtsov, N. B. (2020). Two separate cases: Complex chromosomal abnormality involving three chromosomes and small supernumerary marker chromosome in patients with impaired reproductive function. Genes, 11(12), 1511.