Question

Nisha was found to be affected with a genetic disease. The genetic counselor Dr. Dasgupta asked her to gather information about her lineage. Dr. Dasgupta then made a pedigree chart for four generations based on the information provided by Nisha. From the following pedigree chart, what can you infer about the inheritance pattern in Nisha's family?

• A. Autosomal dominant
• B. Autosomal recessive
• C. X-linked dominant
• D. X-linked recessive

Answer 1

The correct option is C X-linked dominant

The X-linked dominant disorder is expressed in the presence of homozygous as well as heterozygous condition. The gene responsible for the disorder is located on the X-chromosome. The disease may be expressed in both females and males but the males are more susceptible as they carry only one copy of the X chromosome. When a female is affected, the progeny will have 50% chance for the offspring to inherit the disease. When a male is affected, all his daughters will be affected, but none of his sons will be affected.

Thus, the correct answer is option C.