Bio Question about colorblindness

[missDDS]

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I was looking on wikipedia, and it said that many of the genes for color vision are on the x chromosome. I understand thatthe frequency of colorblindness is less in females because they have to have both alleles since one of the x chromosomes is inactivated, but does that mean that males dont have any genes for color vision on their y chromosome so they solely rely on the x chromosomes allele??

thanks

 

[drpsuedonym]

Actually the reason that males are more likely than females to be affected by sex linked diseases (such as colorblindness) is that these diseases are usually recessive. Since the disease causing allele is recessive (say b), in males it ends up causing a disease phenotype since there is no other X chromosome to cover it. In females, even if one chromosome has the rare recessive allele, the other one is likely to have the dominant allele which would mask the recessive allele. The chances of having two (rare) recessive alleles are very slim, which is why females don't often get sex-linked recessive disorders. In males, the Y chromosome doesn't have the corresponding allele, so it can't mask the recessive allele on the X chromosome.