Final answer:
A single nucleotide polymorphism is associated with a disease trait based on its genetic linkage to that trait, answer a) Linkage. Genetic linkage refers to the phenomenon where closely located alleles on a chromosome tend to be inherited together, and this concept is key in genetic mapping and understanding heredity.
Step-by-step explanation:
A single nucleotide polymorphism can be associated with a disease trait based on its genetic linkage to that trait. The correct answer to this question is a) Linkage. Genetic linkage is the linkage phenomenon in which alleles that are located near each other on the same chromosome are more likely to be inherited together. This concept is central to the study of heredity and the mapping of genetic markers, which are genes or sequences on a chromosome with a known location that is associated with a specific trait.
Observations that certain traits are inherited together led to the discovery of genetic linkage by studying patterns of trait inheritance. For instance, geneticists have used linkage analysis in conjunction with genetic markers to map the location of disease-causing genes in the human genome. This method has been instrumental in identifying genes such as the BRCA genes, which are linked to breast and ovarian cancers.