Genetically modified primates that glow green and pass the trait on to their offspring could aid the fight against human disease. Scientists are on their way to create these, which can become one of the biggest businesses ever created especially in the pharma field.

Though primates that make a glowing protein have been created before, these are the first to keep the change in their bloodlines. Future modifications could lead to treatments for a range of diseases.

The “transgenic” marmosets, created by a Japanese team, have been described in the journal Nature. The work raises a number of ethical questions about deliberately exposing a bloodline of animals to such diseases.

Scientists have managed to modify the genes of many living organisms in recent years, ranging from bacteria to mice. Mice have been particularly useful experimental models for studying a wide range of human diseases as modified genes are passed on from parents to progeny.

However, mice are not useful for some human diseases because they are not sufficiently similar to produce effects that are meaningful to human disease. Studies of mice with Alzheimer’s disease, for example, were stymied simply because their brains were too small to scan at sufficient resolution.

So, once the modified monkeys become a reality, our ability to understand the human system is expected to improve vastly.