Why is it essential that genetic markers used in mapping disease genes be polymorphic?
A) If the marker isn't polymorphic, its position cannot be known.
B) If the marker isn't polymorphic, then it's impossible to use genetic mapping techniques to establish an association between the marker and the disease gene.
C) If the marker isn't polymorphic, it cannot be physically linked to a gene associated with human disease.
D) If the marker isn't polymorphic, then it will not be inherited in any predictable manner.

Question

Quizplus · Accepted Answer

Polymorphic genetic markers are necessary for genetic mapping techniques to work because they allow for the detection of allelic variation (different versions of the same gene) within a population. This allelic variation can be used to establish an association between the marker (and its location on the chromosome) and the disease gene. Non-polymorphic markers serve no use in mapping disease genes because they provide no information on allelic variation.

Why Is It Essential That Genetic Markers Used in Mapping