The researches find that the Environmental change is one of the things that can produce big; serious mutations in our DNA that can quickly lead to disease; such as cancer caused by radiation. But our DNA also contains many tiny hidden mutations. While they initially have no effect on us thanks to a box of genetic tricks our bodies use to protect us, these “cryptic” variations can build up over many generations and then be brought to life by big environmental changes.
Hidden Changes In DNA
Recent research has shown just how important these cryptic variations are to evolution. There’s a chance they could be behind the growing risk of problems such as diabetes; cancer and heart disease; and could even produce new diseases. But these mutations also be hidden gifts from our ancestors that enable us to adapt more quickly to the issues we face; from medical conditions to climate change.
Changes to DNA combined with the process of natural selection are what allow species to evolve. Some genetic variations provide a selective advantage and the individuals who have them are more likely to survive and pass on their genes; gradually spreading them throughout the species. Any changes that are a disadvantage reduce the survival or reproductive chances for an individual and are less likely to be passe to future generations. Cryptic genetic variation gives us a third alternative.
Provide a selective advantage
Some changes in DNA have little or no effect; giving neither an advantage or disadvantage but slowly building up over generations. These variations hide in various ways. For example; simple organisms are able to reduce the impact of changes in the environment on their biological functions using a process known as canalization. This means minor changes to their DNA don’t cause visible differences.
Sometimes, genes are even duplicated in different parts of the DNA, so that there is redundancy in the system. Any changes in one gene can then be hidden by the others. In complex lifeforms, many new variations also go unseen because we have two versions of most of our genes (one from mum and one from dad); and one of the versions is dominant over the other.
Cryptic genetic variations are recessive (not dominant); in this relationship and so under normal conditions do not show.There are also some very minor changes that don’t cause any real change to the biochemistry of the organism. They perhaps swap one component in a protein for something very similar.