ob/ob mouse

Spontaneous single-gene loss-of-function obesity mutants have been most useful for understanding energy-regulation pathways, but such defects account for only a minor proportion of human obesity.

Artificial mutagenesis can accelerate mutant generation, but phenotyping cost and the need for strong heterozygous effects have limited progress for understanding energy regulation.

Seasonal and non-human-primate models may offer useful insights into body-fat regulation, but exotic models are constrained by underdeveloped genetic tools and difficulty establishing laboratory colonies.

Animal models have been a cornerstone for studying energy balance, environmental effects, diet responses, and pharmaceutical development in obesity research.