Final answer:
The most common model system used for studying Huntington's Disease (HD) is the transgenic mouse model. Other models include fruit flies, zebrafish, and iPSCs, which all contribute to the understanding of HD pathogenesis and treatment development.
Step-by-step explanation:
The model systems used for studying Huntington's Disease (HD) include various animal and cellular models. The most common model systems are transgenic mouse model, which express the human HD gene with an expanded CAG repeat sequence, leading to the progressive development of HD-like symptoms. Other models include drosophila (fruit fly), zebrafish, and induced pluripotent stem cells (iPSCs). These models help in understanding the pathogenesis of HD and in the development of potential therapies.
Among these, the transgenic mouse model is the most widely used due to its similarity to human HD, including motor and cognitive dysfunction, as well as neuropathological changes. Researchers use this model to study the disease's progression and to test the efficacy of potential treatments.