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  • It’s a fun playground question, Is my red like your red? Well if youre colorblind,

  • your red is probably a lot like your green.

  • Hey everyone, Julia here for DNews

  • Being colorblind not as rare as you’d think. Around 7%–10% of men have some form of what

  • is commonly called red-green color blindness.

  • In colorblind people, 75% have trouble with green, while only 20%

  • have issues with seeing red.

  • It’s not like those colors don’t exist for them. Mostcolorblindpeople can

  • actually see these colors when theyre bright, but if theyre dull or muted in some way,

  • they started to get a little hard to tell apart.

  • Most men get the gene from their mother’s father. It’s a genetic mutation on the X

  • chromosome, which means if men get that copy of that gene, they will express it, or experience

  • it. Whereas most women have two XX chromosomes, so sometimes one x will have the mutation

  • and the other will be just fine and kind of overrides the mutation.

  • To understand what exactly this mutation is doing, let’s take a closer look at the eye.

  • The back of your eyes have a lining filled with photoreceptors. Which means cells that

  • can sense light. Across the animal kingdom there’s quite a few kinds of these cells.

  • But humans have only two. Rods and cones. While rods help us see in low light situations,

  • they see the world in mostly black and white. Cones on the other hand, help us see a rainbow.

  • Three different kinds of cones, each absorb different wavelengths of light. Short, long

  • and medium.

  • Basically when one of the genes get mutated, one or more of these cones don’t work right.

  • The most common form of color blindness, red-green, occurs when medium wavelength sensing cones

  • don’t develop properly. This is called Dichromacy. Monochromacy occurs when two or more of the

  • light sense cones can’t work, inducing an almost total color blindness.

  • Less severe is "anomalous trichromacy". Where the cones work.. kind of. Theyre anomalous,

  • or different in some way. So some people might have trouble distinguishing between shades

  • of colors. A rare condition, achromatopsia, is the inability to see any color. They literally

  • see the world in black and white.

  • On the other end of the spectrum, some people see MORE colors. Tetrachromacy occurs when

  • someone, almost always a woman, has a fourth type of cone cell. But not a single case was

  • actually found until fairly recently.

  • The idea that some people might have a fourth cone was put forward in the late 1940s by

  • Dutch scientist HL de Vries. After studying color blindness in men, he thought that maybe

  • their daughters might carry the mutation too. Since the mutation is carried on the x chromosome,

  • that means women with the gene would have three normal cones, but ALSO the mutation.

  • Equalling a total of four types!

  • But after searching and searching scientists couldn’t find a single person with this

  • condition until 2010. It seems that it takes training to unlock the powers of this fourth

  • cone. Concetta Antico works as an artist and sees shades we can’t even imagine. She sees

  • pink in moonlight and red in green leaves. But it’s not all sunshine and roses, she

  • says going to the supermarket is like “a trash pile of colour”. While genetics aren’t

  • all that rare, maybe up to 12% of women have the gene, it takes training to really see

  • all the possibilities, like becoming a painter.

  • So no, you probably aren’t a tetrachromat and no, that alone doesn’t prove or do anything

  • really. Sorry to burst your bubble. On the other hand though, you can still lose your

  • sense of color even if you don’t have the gene due to eye, nerve, or brain damage, or

  • even exposure to certain chemicals. Or some people’s ability to distinguish colors can

  • fade over time. The cones just get worn out. Over half of people 85 or older have some

  • trouble seeing colors. according to a study published in Optometry and Vision Science.

  • As you get older the optical media within the lens fades and yellows. So some greens

  • appear more yellow.

  • So enjoy that color while you can kid. It won’t last forever. So excuse me, i’m

  • going to go take photos of a sunset or something.

  • Speaking of colors, have you ever wondered if seeing red makes you angry? Check out this

  • video to find out how colors affect your mood!

It’s a fun playground question, Is my red like your red? Well if youre colorblind,

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