Minute to Understanding: What is an allele?

What is an allele? Well, alleles are matching genes; one from our biological mother, one from our biological father. We have two copies of every gene (strings of code that drive some biological function on our chromosomes).

They can be identical, but they can often have slight differences. Alleles, therefore, include all the variant forms of a particular gene. This combination of similarities and differences can have important effects within our body.

What makes these allele variations important? The way that two different alleles interact with each other can sometimes result in different, observable in a person. For example, a dominant allele can override the traits of other recessive alleles, and it is these properties that help decide things like a person's eye and hair color. In this case, alleles that code for brown eyes are dominant over the recessive alleles that code for blue eyes.

Alleles do much more than just decide physical traits. These complex combinations also influence our risks for developing certain diseases, how we react to medications, and even if we develop allergies to certain things. Our genetic makeup, also called our genotype, is decided by the pairs of alleles in our DNA. This elaborate genetic tapestry, including dominant and recessive alleles, are what help decide how we look and live day to day.