In the context of genetic disorders, consider the following :
A woman suffers from colour blindness while her husband does not suffer from it. They have a son and a daughter. In this context, which one of the following statements is most probable) correct ?
Answer:
(d)
Core Books/NCERT
The probability of children inheriting color blindness depends on the genetics of the parents. Color blindness is a sex-linked recessive trait, linked to the X chromosome. A female has two X chromosomes (XX) and a male has one X and one Y chromosome (XY). Option 1: Both children suffer from colour blindness: This is unlikely because the father, who does not have the trait, would pass his normal X chromosome to the daughter. Option 2: Daughter suffers from colour blindness while son does not suffer from it. This is not possible because the daughter would receive a normal X chromosome from her father, and should not express color blindness. Option 3: Both children do not suffer from colour blindness. This is not very probable; while the daughter is likely not to inherit color blindness, the son would inherit the X chromosome from the mother (that carries the trait) and become color blind. Option 4: Son suffers from colour blindness while daughter does not suffer from it. This is the most probable scenario. The son would inherit the X chromosome carrying the defective gene from his mother and become color blind. The daughter, receiving a normal X chromosome from her father, would not.