Researchers have found that how mutations in a gene long identified to be linked with early-onset of Alzheimer's disease cause the brain disorder.

Researcher Ralph Nixon, MD, PhD, Professor of Psychiatry and Cell Biology at the New York University Langone Medical Center and Director of the Center for Dementia Research at the Nathan S. Kline Institute for Psychiatric Research, says, ''We think we have the principal mechanism by how the gene is affected and causes the early onset of Alzheimer's".

Nixon's group discovered that the gene generally aids in clearing away waste from the brain, but the mutation hinders its capability to do so.

Nixon tells WebMD that the finding might ultimately result in treatments not only for early-start Alzheimer patients, but also for the more widespread type, which crops up later in life.

According to the Alzheimer's Association, around 5.3 million Americans are suffering from Alzheimer's, the brain disorder that comprises loss of memory and failure of other intellectual skills.

Of this 5.3 million, nearly 200,000 have the early-onset type.

Fifteen years back, researchers learnt that mutations in a gene, called presenilin 1, were related with early-onset Alzheimer's that can impinge on people as young as in their 30s.