Two unaffected parents have a child with a genetic condition. What can be concluded?
Answer and explanation
Correct answer: A. The condition is likely to be recessive, and both parents are heterozygous carriers of the allele
- Step 1: If the allele were dominant, an affected child would need an affected parent. Step 2. So the allele is recessive and both parents must carry one copy, each passing it on. Answer: recessive, with both parents carriers. Why not the others: mutation or sex linkage is not the only explanation, and a dominant allele would show in a parent.
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