Auckland researchers instead tested the brains of people who had died from the disease. Unlike with the rodents, they found there was no change in one region and a "significant" increase in the production of new brain cells in the other, said senior anatomy lecturer Maurice Curtis.
"It gives hope for people with Huntington's disease. The fact that repair goes on at all spells hope for future therapies aimed at harnessing the brain's own stem cells," she said.
The study was part of an eight-year project on how the brain tries to repair itself over the course of the disease.
Huntington's was caused by a single cell mutation, said Curtis. "That's a tragedy of the disease - it is thrust upon them by their genes."
Huntington's Disease Association spokeswoman Jo Dysart said the findings gave families hope for the future: "Finding cause and a potential cure are critical."
The study is due to be published in the Journal of Neuroscience this month.