According to the given information, wild-type allele of a gene has an A—T base pair at a particular location in its sequence, and a mutant allele of the same gene has a G—C base pair at the same location. Apart from this change, the sequences of the two alleles are same. Based on above information, a question is asked as whether this information tells us anything about the dominance relationship of the allele. If yes, we need to explain why. If no, we need to explain why not. Introduction: Each individual carries a pair of allele responsible for a particular trait. Expression of phenotype in the individual is dependent on allelic combination. Sometimes, either one or both copies of the allele get mutated and are unable to express. In this condition, normal (wild type) allele dominates and represses the effect of the mutant allele. When alleles are present in heterozygous form, dominant allele is responsible for observed phenotype in progeny; recessive phenotype is observed when both copies of alleles are recessive (mutant). When alteration occurs in nucleotide sequence during DNA replication , purine is replaced by purine, i.e., A G or G A and pyrimidine replaced by pyrimidine, i.e., T C or C T. These types of alteration are termed as transition mutation.

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Chapter 4, Problem 36P

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According to the given information, wild-type allele of a gene has an A—T base pair at a particular location in its sequence, and a mutant allele of the same gene has a G—C base pair at the same location. Apart from this change, the sequences of the two alleles are same.

Based on above information, a question is asked as whether this information tells us anything about the dominance relationship of the allele. If yes, we need to explain why. If no, we need to explain why not.

Introduction:

Each individual carries a pair of allele responsible for a particular trait. Expression of phenotype in the individual is dependent on allelic combination. Sometimes, either one or both copies of the allele get mutated and are unable to express. In this condition, normal (wild type) allele dominates and represses the effect of the mutant allele. When alleles are present in heterozygous form, dominant allele is responsible for observed phenotype in progeny; recessive phenotype is observed when both copies of alleles are recessive (mutant).

When alteration occurs in nucleotide sequence during DNA replication, purine is replaced by purine, i.e., A G or G A and pyrimidine replaced by pyrimidine, i.e., T C or

C T. These types of alteration are termed as transition mutation.

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