Question

which of the following is not a sex - linked inherited disorder?
a cystic fibrosis
b color blindness
c hemophilia
d muscular dystrophy

Explanation:

• Cystic fibrosis: It is an autosomal recessive disorder. The gene responsible for it is located on an autosome (not a sex - chromosome).
• Color blindness: It is a sex - linked (X - linked recessive) disorder. The genes related to color vision are located on the X - chromosome.
• Hemophilia: It is an X - linked recessive disorder. The genes for blood - clotting factors (affected in hemophilia) are located on the X - chromosome.
• Muscular dystrophy (Duchenne muscular dystrophy, a common type): It is an X - linked recessive disorder. The dystrophin gene (mutated in DMD) is on the X - chromosome.

Answer:

A. Cystic fibrosis