Neurodegeneration in Down syndrome may begin shortly after birth

Signs of neurodegeneration in individuals with Down syndrome may start as early as birth, a critical stage of brain development, a new study shows. The research, from investigators at the Waisman Center, University of Wisconsin–Madison, provides an atlas of early brain development in Down syndrome that could inform potential targeted treatments to address the developmental and degenerative aspects of the condition.

Down syndrome, caused by an extra copy of the 21st chromosome, is the most common genetic cause of intellectual disability. Most individuals with the condition - more than 90 percent - go on to develop Alzheimer's disease in adulthood, but research shows that their brains start undergoing neuroinflammation and neurodegeneration many years before they present signs of dementia. The new study, published in Science, reveals that this process starts as early as zero to three years of age, and involves a widespread dysregulation of genes.

Neuroinflammation is the activation of an immune response in the brain. Chronic inflammation can cause neurons to die, or degenerate, and is a hallmark of neurodegenerative diseases like Alzheimer's.

It was known that these neuroinflammatory processes can be observed at their early 20s, but we are showing in our paper that at birth you already see this very pronounced neuroinflammation and signatures of neurodegeneration while the brain is still developing," says