The chance that the son of a normal vision female and a color deficient male will be color deficient is zero.
Red-green color deficiency is quite common in males. This condition affects about eight per cent of males and only 0.5 per cent of females. This may lead some to guess that the son in this situation would be color deficient, but this is not the case. The gene for color deficiency is recessive and the normal vision gene is dominant. The gene for color deficiency is carried on the X chromosome. Males are more likely to be color deficient because they carry only one X chromosome.
If a female with normal vision (not a carrier for color deficiency) and a color deficient male have a son, there is no chance their son will be color deficient. Although color deficiency is more common in males than in females, in this situation the only way for a male to be born color deficient is if his mother is a carrier of this gene. The mother in this scenario carries the dominant normal vision gene. Carriers have the mutated allele, but only display characteristics of the dominant normal vision gene. Color blind males pass down the recessive gene to their daughters. These daughters become carriers of the color deficient gene. In order for girls to be color deficient, they would have to inherit the mutated gene from both a color blind father and a carrier mother.
The most common cause for color deficiency is genetics, but there are other factors that may cause the condition. The son in this situation could not be born color blind, but it is possible he could develop color deficiency due to physical trauma to his eyes or possibly due to brain damage. Contact with harmful chemicals can also cause color deficiency in some cases.
Red-green color deficiency is quite common in males. This condition affects about eight per cent of males and only 0.5 per cent of females. This may lead some to guess that the son in this situation would be color deficient, but this is not the case. The gene for color deficiency is recessive and the normal vision gene is dominant. The gene for color deficiency is carried on the X chromosome. Males are more likely to be color deficient because they carry only one X chromosome.
If a female with normal vision (not a carrier for color deficiency) and a color deficient male have a son, there is no chance their son will be color deficient. Although color deficiency is more common in males than in females, in this situation the only way for a male to be born color deficient is if his mother is a carrier of this gene. The mother in this scenario carries the dominant normal vision gene. Carriers have the mutated allele, but only display characteristics of the dominant normal vision gene. Color blind males pass down the recessive gene to their daughters. These daughters become carriers of the color deficient gene. In order for girls to be color deficient, they would have to inherit the mutated gene from both a color blind father and a carrier mother.
The most common cause for color deficiency is genetics, but there are other factors that may cause the condition. The son in this situation could not be born color blind, but it is possible he could develop color deficiency due to physical trauma to his eyes or possibly due to brain damage. Contact with harmful chemicals can also cause color deficiency in some cases.
