Genetic clues identify TB's origins, immunity factors
Specific genes predispose people to being more susceptible to contracting TB infections, and understanding these processes will help health professionals design better vaccines to treat the disease. The research team conducted the genome-wide association study to determine which genomes impact a person’s susceptibility.
The scientists compared genomes from 5,500 TB patients to those from 5,600 control subjects. The total genetic variants amounted to approximately 7.6 million.
ASAP1, a gene located on Chromosome 8, is the gene responsible for a person’s level of susceptibility to TB. It has a protein that expresses dendritic cells, which are crucial to the immune system's response against pathogens.
"Our study provides a new insight into biological mechanisms of TB," lead researcher Sergey Nejentsev from Cambridge University's department of medicine said. "TB is a major global health problem and the threat of drug-resistance means that we urgently need to develop new ways of fighting back. In the future, it may be possible to target immune pathways that involve ASAP1 to design efficient vaccines for TB prevention."
TB, caused by a Mycobacterium tuberculosis infection, was transmitted to 9 million people in 2013, 1.5 million of whom died. More than 95 percent of the TB fatalities occur in the world’s low- and middle-income countries, and one in 10 people fully develops active TB. One-third of the 7 billion people on earth have latent TB, which is a TB infection without the obvious symptoms.