Questions – both practical and ethical – exist for application in humans
The focus on research into Down syndrome concentrates upon genetics because of the common link between all individuals with the condition – an extra copy of chromosome 21.
However, recent work on mouse models suggests the ability to treat and potentially reverse the condition. Researchers from the University of California San Francisco and Baylor College of Medicine focused on the protein-producing cells in the brains of mice with Down syndrome, leading them to the discovery that the animals’ hippocampus regions produced 39 percent less protein than those of typical mice.
Down syndrome is a cognitive disability that can impact a person’s ability to learn, an untreatable and irreversible lifelong condition. However, the research published in Science last month raises all sorts of possibilities, ethical questions, and potential dilemmas for scientists and future generations.
“The cell is constantly monitoring its own health,” researcher Peter Walter said in a press release. “When something goes wrong, the cell responds by making less protein, which is usually a sound response to cellular stress. But you need protein synthesis for higher cognitive functions, so when protein synthesis is reduced, you get a pathology of memory formation.”
Down syndrome is the most common genetic cause of intellectual disability. People born with the syndrome have deficits in learning and memory. They also have an increased risk of developing Alzheimer’s disease by middle age.
Compared with normal mice, protein production was reduced by about 40% in the hippocampus region in the brains of Ts65Dn mice. The hippocampus plays a central role in learning and memory formation. Further experiments showed that the ISR was persistently active in the hippocampus of the Ts65Dn mice.
To assess whether Down syndrome may also involve these changes, the team measured ISR activity in samples taken from brains and cells donated by people with Down syndrome. The samples had increased ISR activity as well.
“We started with a situation that looked hopeless,” Walter said. “Nobody thought anything could be done. But we may have struck gold.”
SOURCES: Futurism, NIH
