A child has PKU disorder, but neither parent has PKU. What is the genotype of the parents? Give reason for your answer.

Explanation

To determine the genotype of the parents of a child with Phenylketonuria (PKU) disorder, we need to understand the genetic basis of the disorder and how it is inherited.

### Step-by-Step Solution:

1. **Understanding PKU**:
- PKU (Phenylketonuria) is an autosomal recessive disorder. This means that for a child to express the disorder, they must inherit two copies of the mutated gene (one from each parent).

2. **Genotype of the Child**:
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