Epistasis refers to the interdependence of separate genes and their effects. These interactions can be vast and subtle, and create many unexpected outcomes. It also enables a huge diversity of phenotype and potential for evolution. In this silly example, a gene inducing baldness creates an outcome that interjects the outcome of genes for hair colour, as the hair would not get to show itself anyway.
Through this interaction, the different alleles for the colour gene are suddenly and non-linearly disabled.
Continuous variation can also be seen with genetically-induced traits e.g. height, hair colour; where outcomes are found on a spectrum with high diversity, and is also subject to environmental influence e.g. nutrition, light exposure.
Phenotypes can be subject to the action of multiple genetic components. This is polygenic inheritance. For example, heart function is not dependent on a gene. It is a cumulative outcome of many different genes that determine muscle fibres, cell membrane proteins, nerve function, etc.
You're such a G. Helped me so much, finally found someone who breaks biology down into something I can understand!!!
Alex Contact Form
Hi! I have recently finished my first year doing biology at uni and I subscribed to you back when I was doing AQA A levels (glad I don’t live in Wales after watching this vid lol) and you and your website helped me so much. Just wanted to say it’s so nice to see you
Mr Peanutbutter YouTube
OMG that’s great! Actually just helped me with my homework
mabelbarc The Student Room
I’ve struggled so much with feeling overwhelmed with biology revision, and I don’t know where to start. But your website is just what I need! It tells me all the information I need, and the knowledge I need to then build on, and it’s written in a way that soaks straight up into my brain!
Prettyhetty The Student Room
I bookmarked the site
translucent The Student Room