Final answer:
None of the options A) Late age of disease onset, B) Efficient selection against rare recessive disease-causing alleles, and C) New mutations contribute to keeping low-fitness alleles in our gene pool. The correct answer is E) None of the above (A-C) contribute.
Step-by-step explanation:
The question asks which factors do not contribute to keeping low-fitness alleles in our gene pool. The correct answer is E) None of the above (A-C) contribute to keeping low-fitness alleles in our gene pool because:
- (A) Late age of disease onset may allow individuals to reproduce before the disease impacts them, thus passing on the allele.
- (B) Efficient selection against rare recessive disease-causing alleles is actually a factor that would tend to remove such alleles from the gene pool, unlike A and C.
- (C) New mutations can introduce low-fitness alleles into the gene pool.
Concepts such as the frequency of beneficial alleles, chance effects on the gene pool, successful reproduction, and the presence of genetic abnormalities and susceptibility to disease play roles in determining the prevalence of certain alleles within a population. Carriers of deleterious alleles can reproduce and pass on these alleles without expressing the harmful phenotypes if they are heterozygous.