- As  certain species reproduce, there will be some level of variation caused by mutations
- Mutations that are advantageous to survival (known as "adaptive mutations") wil become more common within a species, and passed down to subsequent generations

Smith College

A mutation is a sudden, permanent change in a sequence of DNA. Mutations serve as a primary source for harmful genes, such as the one causing Phenylketonuria (PKU). While many mutations can be detrimental or lethal, they can occasionally be beneficial, conferring an advantage to an individual that enhances their survival and reproductive success compared to others.

Mutation

Breedlove, S. & Watson, N. (2017). Behavioral neuroscience, eighth edition. Oxford University Press.

Behavioral Neuroscience 8th Edition

Researchers study mutations in developmental disorders using many different techniques, many of which involve animal models. In animal models, researchers may be able to perform the following: 

-Site-directed mutagenesis: Researchers mutate a specific gene using this technique.

-Knockout organism: When site-directed mutagenesis has been performed to completely remove a gene, the organism is called a knock-out organism. We cannot always assume that a lack of behavioral changes to a knockout organism means that the gene that has been knocked out is not important to that behavior! 

-Transgenic organism: An organism whose genetic material has been altered by the addition of a gene that is new or somehow modified. This is particularly useful for studying genetic disorders.

Some of these methods can be applied later in an animal's lifespan to deduce the effect of mutations in an adult organism. 

Studying Mutations in Developmental Disorders

Clones are organisms that are genetically identical, and are formed via asexual reproduction. They can provide insight as to the relative influence of genetics and the environment in sculpting a particular behavior. 

Clones

Adaptive Mutations 

A population of bacteria is exposed to a powerful antibiotic, which kills most of the cells. However, a small number of bacteria survive because they possess a sudden, permanent change in one of their genes that was not present in the parent population. Based on this information, what is the most accurate conclusion to draw about this genetic change?

Learn Before

Related