Which of the following is NOT a type of dominance?

• A. Complete dominance
• B. Incomplete dominance
• C. Codominance
• D. Leaky dominance

Answer: (D)

Verified step by step guidance

1. Understand the concept of dominance in genetics: Dominance refers to the relationship between alleles, where one allele masks the expression of another in a heterozygous individual.
2. Review the types of dominance: Complete dominance occurs when the phenotype of the heterozygote is the same as that of the dominant homozygote. Incomplete dominance results in a phenotype that is intermediate between the two homozygotes. Codominance occurs when both alleles in a heterozygote are fully expressed, resulting in a phenotype that shows both traits.
3. Identify the term 'Leaky dominance': This term is not a standard type of dominance in genetics. It may refer to a situation where a dominant allele does not completely mask the effects of a recessive allele, but this is not a recognized category like the others.
4. Compare the given options with standard genetic terminology: Complete dominance, incomplete dominance, and codominance are well-established types of dominance in genetics.
5. Conclude that 'Leaky dominance' is not a recognized type of dominance in genetics, making it the correct answer to the question.