The study focused on the growth of cells which cause diseases like cancer
Genetic "brakes" which could slow down or stop diseases like MS and cancer have been found by scientists.
University of Edinburgh researchers said their findings could lead to new treatments for such illnesses.
It was previously thought that a select group of "master" genes was responsible for controlling the growth of cells which can cause the conditions.
But the team found hundreds of genes interacting and they will now try to find weak spots to halt tumour growth.
Scientists said they believed variations in this network explained why people could develop diseases in different ways.
The team hopes that by identifying weak spots in the gene structure they will be able to stop the growth of tumours, enabling the growth of healthy cells.
Professor David Hume, of the university's Roslin Institute, who led the research, said: "This study has effectively shown us where the brakes are which could slow down or stop diseases like cancer and multiple sclerosis.
"We believe this could lead to treatments and cures for many diseases of the immune system."
The findings are published in the Nature Genetics journal.