People who carry a particular type of gene have natural resistance against typhoid fever according to new research published in Nature Genetics.
The study is the first large-scale, unbiased search for human genes that affect a person’s risk of typhoid and the findings are important because this natural resistance represents of the largest human gene effects on an infectious disease. This work was conducted in patients from Vietnam with findings then replicated in independent patient cohorts from Vietnam and Nepal
Lead researcher, Dr Sarah Dunstan from the Nossal Institute of Global Health at the University of Melbourne said the study involving screening the human genome to look for genes associated with susceptibility to, or resistance from typhoid.
“We found that carrying a particular form of the HLA-DRB1 gene provides natural resistance against typhoid fever. This gene codes for a receptor that is important in the immune response, by recognising proteins from invading bacteria,” Dr Dunstan said.
Typhoid is contracted, by consuming food or water contaminated with the bacteria, Salmonella Typhi or Paratyphi. It has been estimated that typhoid causes 200,000 deaths a year globally, and infects 26.9 million people per year.
“If we can understand this natural mechanism of disease resistance, then we can use this knowledge to help develop improved vaccines for typhoid fever, but also potentially for other invasive bacterial disease.”
The research collaboration was between the Genome Institute of Singapore and Oxford University Clinical Research Units in Vietnam and Nepal.