Are you a Tetrachromat?
Do you carry the genetic mutation that allows you to see up to 9 million more colours than everyone else?
The average human is able to see around 1 million colours. But recent research shows there may be people who can see many more colours than usual.
Neuroscientists from Newcastle University have been looking into the idea of superhuman vision. They have discovered that some people may be able to see up to 9 million more colours than the average person.
What is Trichromacy? (‘Normal’ Vision)
People who have the normal range of colour vision have trichromatic vision. Cones are cells found at the back of the eye, responsible for detecting colour. Those with trichromatic vision have three functioning cone types that detect different light colours. One cone type detects red light, one detects blue, and one detects green. People with trichromatic vision can see around 1 million different colours; combinations of red, blue, and green.
Trichromats can also have limited colour vision. Those who have three functioning cone types, but suffer from colour blindness are said to have anomalous trichromacy.
What is Tetrachromacy? (Superhuman Vision)
People who are tetrachromatic are believed to see around 10 million different colours. Tetrachromatics have four cone types in the back of their eyes (normally people have three). Research shows that people with tetrachromatic vision are
- Always female.
- Carry a gene that results in colour blindness- often have a father who is colour blind.
The theory is that tetrachromats have an extra cone type as a result of a mutation. This is like the mutation that occurs in colour-blindness, yet all the tetrachromat’s cone types are completely functional. This mutation happens on the X chromosome. Women inherit two X chromosomes, so if a mutation occurs on both chromosomes, they have the potential of being a tetrachromat. As men only inherit one X chromosome, any mutations that occur would result in them having anomalous trichromacy.
How Do You Test For Tetrachromacy?
Research is still in progress to see if this condition exists. Because of this, there are no mainstream tests for tetrachromacy. Recent studies predict that up to 12% of women have four cone types, but very few have the capacity to see more colours. If you are a woman who has a father or son with colour blindness you are more likely to be tetrachromatic. But this condition is so rare it is unlikely you will ever know you have it!