On GriefCertificate, WardCunningham talks about ColorBlindness and a few other people chimed in.  Someone mentioned that 10% of all males are color blind to some degree, but most of them actually have weakness to a colour, not blindness, most common is weakness to green (Deuteranomaly), weakness to red (Protanomaly) being less common.  One thing that I wonder about is correlation with other traits.  It may sound silly, but I often find out that some of the best technical guys I know are ColorBlind, LeftHanded or both.  I don't know whether this is just chance or not.

Isn't ColorBlindness one of those male conditions that comes about because men don't have another X chromosome?  Like hemophilia?

''Yes, it's recessive.  Women can be red-green color blind/weak too, but they'd have to have the "bad" gene on both X chromosomes, which is extremely unlikely, except in areas where it is ununally common.''

''And if a woman has the gene for DeuteraNomaly on one X chromosome and that for ProtaNomaly on the other, she can be a TetraChromat -- one who can distinguish colors of four wavelengths, as opposed to most humans who can only see three (red, green, and blue).''

''8 percent of males, 0.5 percent of females - according to http://www.zipmall.com/mpm-art-colorbl.htm -- RobertField'' Most common type is DeuteraNomaly where the perception of green is shifted towards red.

For the first time, researchers have tracked down the genetic cause of red/green color blindness, a vision defect that affects 1 out of 20 men in the United States. The finding may lead to a blood test for the condition, which is now diagnosed using color charts. --Reuters October 31, 1996. 
http://www.cactus.org/~kingman/CVDlast.html

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	* Short story and quick test --  http://www.geocities.com/Heartland/8833/coloreye.html

Note:  Any color blindness test done through your computer monitor will be unreliable, because computer monitors aren't tuned for precisely correct color rendering.

	* Short guide on color blindness issues in web design, with a "safe" palette: http://www.visibone.com/colorblind/

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Empirical confirmation: my father is also both ColorBlind and LeftHanded. -- HelmutLeitner

Some red-green deficiency here, right handed. -- CarstenKlapp

My brother is completely ColorBlind (no colours at all), but he's right-handed.  Last I heard the thinking on handedness was that it was environmental rather than genetic.  Dunno if that's right though.  -- AndyPierce

Well being DownUnder I am ColourBlind ;) and right handed, one of my brothers is left handed and colour blind, he is a better puzzle solver than me.  -- AndrewMcMeikan