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Genes A, B, C, and D are located on the same chromosome. The recombination frequencies (RF) are as follows:What is the most likely order of the genes on the chromosome? Relationship. RF A-B. 8% A-C. 23% A-D. 19% B-C. 10% C-D. 52%

Correct answer: B. CBAD

  • A. BCAD
  • B. CBAD
  • C. ACBD
  • D. ABCD

Explanation

A pair of genes with a larger recombination frequency are likely farther apart, while a pair with a smaller recombination frequency is likely to be closer together. Therefore, we should start with the largest recombination frequency (RF) of two genes. In this case, C and D are the farthest apart, so A and B must be between them. The explanation is given in the image.

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About Inheritance

Mendel's laws explain segregation, independent assortment and the prediction of genetic ratios using alleles, genotypes and phenotypes. The chapter also covers linked genes, recombination and crossing over during meiosis, then applies pedigree reasoning to X-linked recessive traits, which show different inheritance patterns in males and females.

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