Question

Anthropology Question:

Why are females more likely to be carriers for color blindness than to be color blind themselves?

Answer 1

Answer )

Colour blindness is a defect in which the affected person cannot differentiate between colours of RED-GREEN-YELLOW.

Reason :

Colours from the surroundings are perceived through a specialised set of cells called cones. There are three types of cone cells in the retina of the eye, three types bear three different pigments. Any defect in the biochemical pathway of production in these pigments results in colour blindness.

There are three genes which help in the production of these pigments those are :

1)OPN1LW

2)OPN1MW

3)OPN1SW

OPN1LW and OPN1MW genes are present on one of the sex chromosomes( X chromosome to be precise). Wheres OPN1SW is present on the autosome.

The reason why the woman are carriers than affected by this disease:

Woman have two X chromosomes, therefore have two copies of OPN1W and OPN1SW genes. even if one gene is corrupted another copy will come to the rescue. Thereby reducing the risk of colourblindness.

Whereas in men they have one X chromosome and one Y chromosome. If they receive a faulty copy of the X chromosome from their mother they do not have another copy to compensate for its negative effects.

Hence women tend to be carriers than affected whereas men tend to be more colourblind.