Boston (SmartAboutHealth) - Scientists from the Children’s Hospital of Boston are now saying that people living with Down’s syndrome are at a decreased risk of developing many types of cancer.

Down’s syndrom is the most common form of mental retardation, and is caused by an extra copy of chromosome 21.

This extra chromosome, results in people living with Down’s having an additional copy of more than 230 different genes.

Working with mice, the scientists injected some with a gene found on chromosome 21, and saw that the gene appeared to slow cancer growth when those mice were injected with cancer cells.

The scientists, whose study appears in the journal Nature hope that one day their discovery can lead to new treatments for cancer.