Question

Given below is a pedigree chart of a family with five children. It shows the inheritance of attached earlobes as opposed to the free ones. The squares represent the male individuals and circles, the female individuals. Which one of the following conclusions drawn is correct?

• A. The parents are homozygous recessive
• B. The trait is Y-linked
• C. The parents are homozygous dominant
• D. The parents are heterozygous

Answer 1

The correct option is D The parents are heterozygous

Here, in the pedigree chart, since females are also getting affected, it is not Y-linked inheritance.

If the parents were homozygous dominant or recessive, then all progenies would have earlobes like the parents.

Parents with free earlobes produced progenies with attached earlobes which means that both the parents are heterozygous in nature.