RAS question
Gene drive technology is controversial because it can:
Correct answer: (B) Spread a genetic modification through an entire wild population rapidly.
Gene drive technology is controversial because it can rapidly spread a targeted genetic modification through a wild population.
Explanation
Gene drives are designed to bias inheritance: instead of a genetic change passing to about half the offspring under ordinary Mendelian inheritance, a drive can push the chosen genetic element through generations at a much higher rate. The National Academies summary describes gene drives as systems where a genetic element's passage from parent to offspring is enhanced, with the result that a specific genotype can increase from one generation to the next and potentially throughout a population. That is why option B captures the controversy. CRISPR/Cas9 has made laboratory gene-drive work more practical, including mosquito examples linked to malaria control, but the same capacity to spread raises concerns about ecological disruption, uncertain effects outside the target organism, and possible irreversibility.
Why the other options are wrong
- (A) Gene drives have been demonstrated in laboratory organisms, but their defining concern is intended spread through populations, including possible environmental release, not effects limited to the lab.
- (C) A gene drive changes inheritance of a genetic element within an existing species or population; it is not a mechanism for instantly creating a new species.
- (D) Gene drives are proposed for specific problems such as vector-borne disease control, but they do not cure all diseases and do not act as a general medical treatment.
Concept
This tests biotechnology and environmental governance: the science is the altered inheritance pattern, while the policy issue is ecological risk. RAS repeatedly asks such topics because they connect emerging technology with public health, biodiversity, ethics, and regulation.