Question

Why can't recombination frequency exceed 50% (50 map units) in genetic linkage analysis?

A) Recombination frequency is a measure of the distance between genes, and 50% represents the maximum separation possible.
B) The physical limit of chromosome length prevents recombination frequency from exceeding 50%.
C) Recombination frequency reflects the probability of crossover events, and it is statistically improbable to exceed 50%.
D) Genetic maps are designed to have a maximum of 50 map units for simplicity and standardization.

Answer 1

Recombination frequency is capped at 50% in genetic linkage analysis because this represents the point at which genes assort as if they are not linked, either on separate chromosomes or very far apart on the same chromosome.

Step-by-step explanation:

The recombination frequency cannot exceed 50% in genetic linkage analysis because a recombination frequency of 50% indicates that genes assort independently, simulating a situation where genes are on separate chromosomes or are very far apart on the same chromosome. In such cases, the assortment of these genes will mirror that of unlinked genes, which means that in a large number of offspring there will be an equal chance (50/50) of inheriting any combination of alleles from these genes. This 50 map unit cutoff reflects that there is a maximum of 50% chance for alleles to recombine, beyond which it can no longer be determined if they are linked or on separate chromosomes, thus mapping linkage becomes less accurate.