Describe recombination frequency and how it is used to map genes; define cis vs trans configurations.

• A. Recombination frequency estimates distance in centimorgans; cis (coupling) describes mutant alleles on the same chromosome, trans (repulsion) on opposite homologs.
• B. Recombination frequency measures gene expression levels; cis and trans refer to chromosomal coordinates.
• C. Recombination frequency is used to clone genes; cis means alleles are on separate chromosomes.
• D. Recombination frequency determines protein structure; cis and trans describe protein folding.

Answer: (A)