Point Mutations

Point Mutations and Their Vast Array of Traits, Qualities and Drawbacks

Point mutations most often than not spell trouble. Although most of these mutations are considered to be more or less benign, there is usually a risk that even these can lead to loss in protein function and ultimately, to various diseases. Depending on what caused the mutation, what type of mutation it is and how the organism responds to it, there are many potential repercussions that could affect the organism in question, some more negative than others.

What Mutations Can Do

What are point mutations all about, and what are they truly capable of? When considering the prospect of genetic mutations, most people would think of the effects of high energy radiation. However, as we will see, there are many possible causes for these types of mutations, and the effects are not always detrimental. Protein function and even the entire process of cellular reproduction can be modified in some cases. Also, short term, small time effects can result, for example, because of the halting of the cell function at certain stages. The most serious impairment of gene function as a result of a point mutation will typically depend on the location of the mutation itself. If the mutation occurs in an area responsible for protein encoding then the damage can be severe, potentially leading to the loss of stability and/or function within the protein complex.

Specific Point Mutation Changes to Be Considered

It can be extremely important to study the effects of point mutations when they occur in areas revolving around coding. As discussed, these mutations can be severe, however, their severity and impact will also depend on the type of mutation that occurs. This is based on whether or not their transitions or transversions are able to alter the nucleobase structure. Silent mutations, for instance, are benign. They do not change their corresponding amino acids. However, missense mutations are much more volatile, being capable of causing protein loss and disease, if it’s not conservative. Finally, nonsense mutations exchange regular amino acids codons for stop codons, and thus lead to protein truncation – which can eventually cause protein function loss.

What Can Cause a Point Mutation?

The causes of point mutations are well-documented. Nevertheless, there are still many unknowns that have to be studied regarding this issue. When a double stranded DNA molecules creates two separate single strands, the process of point mutation is a distinct likelihood. Also, radiation and chemical reactions can lead to a point mutation when the reactions are severe enough, or environmental properties such as temperature change drastically (extreme heat). High frequency light can affect DNA due to its influence on ionizing electrons. This can lead to reactions between oxygen molecules and free radicals, which can be extremely detrimental to the DNA molecule.

Mutation vs. Adaptation

Not all mutations are neutral or negative. In some cases, mutations can lead to positive changes. This is the case of point germline mutations, which can lead to both positive and negative genetic changes. Advantageous mutations can lead to the organism being fortified in the face of a damaging change, and the mutation being passed down through multiple generations. In this case, point mutations can actually be a viable explanation for the theory of evolution, which would explain how certain changes have happened in the genetic makeup of evolving organisms.