Question

2. Refer to the family pedigree shown here. In generation |, one parent is affected by the gene mutation and one parent isn't. In

generation Il, all three children are affected by the gene mutation. What can you conclude about this gene mutation?

A. This gene mutation is a recessive disorder.

© B. All children born in future generations will be affected by this disorder.
© C. This gene mutation is a dominant disorder.

© D. The generation | mother is a carrier of this gene mutation.

Answer 1

C is the answer

Answer 2

Answer: The correct answer is option c

Step-by-step explanation:

According to the information provided, it is clear that the trait is dominant in nature. In addition, the parent who was affected by the mutation must be homozygous dominant in genotype.

Dominant traits do not skip generation in the pedigree. Similarly, this trait was also expressed in the successive generation due to which it can not be the case of recessive trait. Thus, option a is incorrect.

All children born in future generations will not be affected by this trait. For example, if one parent is heterozygous dominant and one parent is homozygous recessive then there are 50 percent chances that the offspring will not carry the disease. Thus, option b is also incorrect.

In dominant trait, a person can not be a carrier as presence of one allele results in the expression of the disease. Thus, option d is also incorrect.

Only when the disease is dominant and the parent is homozygous dominant then only it is possible that all the offspring will carry the disease.

Similar cross is shown below for reference.