Wife is PTC non-taster and husband is PTC taster. Their son is taster but daughters are non-tasters. This is not a sex linked trait. Which pedigree is correct ?

Options

A.
B.
C.
D.

Answer

To solve the question regarding the PTC tasting trait in the family described, we need to analyze the genetic inheritance of the trait based on the information provided.

### Step-by-Step Solution:

1. **Identify the Traits**:
- PTC tasting is a dominant trait represented by "B" (taster).
- PTC non-tasting is a recessive trait represented by "b" (non-taster).

2. **Determine the Genotypes**:
- The wife is a PTC non-taster, so her genotype is **bb** (homozygous recessive).
- The husband is a PTC taster, but since their son is a taster and their daughters are non-tasters, the husband must be heterozygous, so his genotype is **Bb** (heterozygous).

3. **Analyze the Offspring**:
- The son is a taster, which can be either **BB** or **Bb**. Since he is a taster, he must be **Bb**.
- The daughters are non-tasters, which means they must have the genotype **bb**.

4. **Construct the Pedigree**:
- The pedigree should show the wife (bb) and husband (Bb) having one son (Bb) and two daughters (bb).
- The son inherits the taster allele from the father and the non-taster allele from the mother, resulting in the genotype Bb.
- The daughters inherit the non-taster allele from both parents, resulting in the genotype bb.

5. **Select the Correct Pedigree**:
- Based on the analysis, the correct pedigree will depict the wife as a non-taster (bb), the husband as a taster (Bb), one son as a taster (Bb), and two daughters as non-tasters (bb).

### Conclusion:
The correct pedigree is option A, where the wife is a non-taster (bb), the husband is a taster (Bb), the son is a taster (Bb), and the daughters are non-tasters (bb).