Year 10 Science · Unit 1 · Lesson 9
Challenge Worksheet
Learning Goals
What if…?
Scenario
Scientists propose releasing a gene drive in north Queensland to eliminate the Aedes aegypti mosquito, the main carrier of dengue fever in Australia. The gene drive is engineered using CRISPR and would spread a gene that prevents females from reproducing, eventually crashing the wild population. North Queensland records hundreds of dengue cases each year. Once released, the gene drive cannot be recalled, it would spread through the entire regional mosquito population within several years. The proposal is currently awaiting ethical review.
(a) Predict the likely impact on dengue fever case numbers in north Queensland if the gene drive is successfully released. Use scientific reasoning in your answer.
(b) Aedes aegypti mosquitoes are part of the local food web, they are eaten by birds, bats and spiders, and their larvae are consumed by fish and aquatic insects. Predict at least two possible ecological consequences of significantly reducing or eliminating this mosquito species from the north Queensland ecosystem.
(c) The gene drive cannot be reversed once released. Using ethical reasoning, argue either for or against proceeding with the release. Your argument must acknowledge and respond to the strongest counterargument.
1. He Jiankui edited human embryos in China in 2018 without proper regulatory approval or fully informed consent from parents. Identify two specific reasons why germline editing of human embryos remains banned in most countries, even when the intended outcome (e.g. HIV resistance) might be beneficial.
2. Compare the reversibility of CRISPR somatic gene therapy in a hospital patient versus a gene drive released into a wild population. Why does reversibility matter ethically?
Wrap Up
In one sentence, explain why the irreversibility of a gene drive makes it ethically distinct from other CRISPR applications.