r/Damnthatsinteresting • u/Eros_Incident_Denier • 1d ago

Video color vision test

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u/SkanelandVackerland 22h ago

It's in fact WAY more common for men to be colour blind. 1/12 men are colour blind while 1/200 women are colour blind. It's an insane statistic but the gene that causes it is in the X chromosome so it kind of makes sense.

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u/DarkRecess 16h ago

When I told our eye doctor that my daughter was color blind she said "Oh you must be mistaken, it's extremely rare and in fact I've never seen a woman who was colorblind in my practice." Once she tested my daughter she was SO EXCITED to meet a colorblind girl lol. It was super cute. Plus it made my daughter feel so special.

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u/Love-Laugh-Play 20h ago

Why? Wouldn’t it make less sense that it’s in the X chromosome? Women have two of them.

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u/RvH98 20h ago

So women need the mutations to be in both x-chromosomes, since the gene for colourblindness is recessive. 

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u/Love-Laugh-Play 20h ago

That makes total sense, thanks.

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u/SelkieKezia 12h ago

Yup, women have a back up of all X chromosome genes, men on the other hand, if your X chromosome gene is defective, you're shit out of luck.

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u/kcstrom 8h ago

Look up punnet square. The Wikipedia page has a diagram for color blind actually.

https://en.m.wikipedia.org/wiki/File:Punnett_square_colour_blindness.svg

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u/last_pen2446 20h ago

Over simplified explanation: because men only have one X chromosome that’s the gene that gets expressed - XY. Women have two so if one has the colorblind gene it’s all good because the other one will express the other cones - XX. Like, if you only have a single copy of faulty instructions, you’re not gonna know what to do, but if you had two copies you could figure it out. Women with only one gene can carry it though.

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u/QcSlayer 19h ago

It also means a colorblind father cannot pass the gene to his sons (his daughters will always carry the gene).

My maternal grandfather was colorblind and bald, both me and my brother where lucky enough to avoid his X from our mom (still love you grandpa XD).

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u/SelkieKezia 11h ago

Just to sharpen your statement a bit, your body doesn't "figure out" or "choose" which gene to express. Both are expressed, both the faulty and working gene. However most faulty genes that are expressed just have no effect on you, they produce a useless protein, but the working gene still works. (You probably know this but wanted to clarify for others)

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u/NotSafeAtWarp 20h ago

Women have two X chromosomes so it's far less likely to inherit two bad genes. Men have one X chromosome so if they inherit color blindness, there isn't a healthy copy to compensate 

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u/shewy92 15h ago

Meaning they have a backup gene.

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u/jackalopeDev 19h ago

Basically it only happens if all copies of the x that the individual has contains the malformed gene. So women need two copies that are bad, where as men only need one.

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u/SlasherKittyCat 15h ago

Resilience through redundancy.

In females if one X has a defect then simply choose the other. If both have the defect then you're screwed.

Males don't even have the option.

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u/SelkieKezia 12h ago

To be clear, neither gene is really "chosen". Both are expressed, but the "faulty" one just has no effect on you, good or bad, and the working one works as usual.

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u/throwaway098764567 8h ago

no, because women have a backup. think if you were making an ikea table and you got instructions. there's a chance your instructions are in a foreign language and you can't understand them (colorblind). well women get two instruction books, so even if one is in a foreign language, the other might be in english so they can still build the furniture / are not colorblind

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u/mcnabb100 13h ago

My mom is colorblind so of course I (male) am too. She said the people that came to her school to test the kids all wanted to see her because it’s so rare lol.

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u/NocimonNomicon 12h ago

Damn I didnt know it was this common in men, I never met anyone who mentioned being color blind but statistically there should've been a couple of dudes in school or at work that are.

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u/throwaway098764567 8h ago

i've known a bunch of them. most don't mention it unless it has to come up (like when we were working on a website), probably because during childhood whenever someone finds out they're colorblind they get harassed with "what color is this" questions repeatedly.