Which statement best explains why mice are common in research?

Which statement best explains why mice are common in research?

• A. Short life span, breed easily, and are biologically similar to humans
• B. Large size and slow breeding
• C. They are the only model used
• D. They have no genetic variation

Answer: (A)

Using mice in research works because they combine a short life cycle, rapid reproduction, and strong biological similarity to humans. A short life span and quick generation turnover let researchers observe aging, inheritance, and disease progression across many generations in a practical timeframe. Easy breeding supports large, cost-effective study populations, which helps achieve statistically reliable results. In addition, mice are small and inexpensive to care for, yet their physiology shares many fundamental processes with humans, making findings more translatable. Researchers also benefit from a vast toolkit: numerous well-characterized strains and powerful genetic modification methods enable precise dissection of gene function and disease mechanisms. The other statements don’t fit as well: being large and slow to breed would be a disadvantage for a model organism, which mice are not; they are not the only model used—different questions call for different animals or systems; and there is genetic variation among mice, especially across strains, so the idea that there is no genetic variation isn’t accurate, even though researchers may use inbred lines to reduce within-group variability.

Using mice in research works because they combine a short life cycle, rapid reproduction, and strong biological similarity to humans. A short life span and quick generation turnover let researchers observe aging, inheritance, and disease progression across many generations in a practical timeframe. Easy breeding supports large, cost-effective study populations, which helps achieve statistically reliable results. In addition, mice are small and inexpensive to care for, yet their physiology shares many fundamental processes with humans, making findings more translatable. Researchers also benefit from a vast toolkit: numerous well-characterized strains and powerful genetic modification methods enable precise dissection of gene function and disease mechanisms.

The other statements don’t fit as well: being large and slow to breed would be a disadvantage for a model organism, which mice are not; they are not the only model used—different questions call for different animals or systems; and there is genetic variation among mice, especially across strains, so the idea that there is no genetic variation isn’t accurate, even though researchers may use inbred lines to reduce within-group variability.