Question

What ratio is expected in offsprings if father is colourblind and mother’s father was colourblind?
A. \[50\% \] daughters are colourblind
B. All the sons are colourblind
C. All the daughters are colourblind
D. All the sons are normal

Answer 1

Hint: Color blindness is simply defined as the inability to see or identify colours such as blue, green, or red. There are a few uncommon circumstances where a person is unable to detect or recognise any colours. A person with this disease also has trouble distinguishing between colours and tints. A colour vision problem or deficiency is another name for this syndrome.
Types of colour blindness- monochromacy and dichromacy

Complete answer:
Option A: Color blindness is a recessive X-linked disease. The father's X chromosome is passed down to the daughters, hence the colorblind father will pass on his affected X chromosome to his daughter. As a result, the carrier female's genotype will be (XcX) and the colorblind man's genotype will be \[\left( {{X^c}X} \right)\] \[\left( {{X^c}Y} \right)\]. Because a son inherits his X-chromosome from his mother, the mother must be colorblind in order for all affected boys to be born. The carrier female's one copy of the afflicted X-chromosome is passed down to \[50\% \] of her sons. Daughters acquire one X-chromosome from their mother and the other from their father; hence, both parents must be colorblind. The disorder will be passed down to \[50\% \] of sons and \[50\% \] of daughters from the carrier mother and colorblind man.

Parent generation: \[{X^c}X\] \[{X^c}Y\]
Gametes:
\[^\;{X^c}{X^c}\] (colourblind girl) \[{X^c}X\] (carrier girl)

 \[{X^c}Y\] (colourblind boy) \[XY\] ( normal boy)

Option B: The carrier female's genotype will be \[\left( {{X^c}X} \right)\], whereas the colorblind man's genotype will be \[\left( {{X^c}X} \right)\]\[\left( {{X^c}Y} \right)\]. Because a son inherits his X-chromosome from his mother, the mother must be colorblind in order for all affected boys to be born.
So, option B is not correct
Option C: Daughters acquire one X-chromosome from their mother and the other from their father; both parents must be colorblind to have entirely colorblind daughters.
So, option C is not correct.

Option D: The carrier female's one copy of the afflicted X-chromosome is passed down to 50% of her sons.
So, option D is also not correct.

Additional information:
There is currently no treatment for this condition. To some extent, photographic frames or filters, as well as eyeglasses with contact lenses, can be utilised to improve the dimension between specific colours. Color blindness symptoms can be alleviated by eating a well-balanced diet.

Note:
Color blindness is a condition that is passed down from both parents. It's a recessive sex-linked condition. X chromosomes contain genes for red-green colorblindness. Males acquire colour blindness only from their mothers because they only have one X chromosome. Females inherit two copies of the X chromosome from both parents.