Tuberculosis-Susceptibility Gene Found in Mice

Scientists have discovered a tuberculosis-susceptibility gene in mice that may help to improve diagnosis and prevent the disease that kills up to 2 million people each year.

They believe the gene, called Ipr1 in mice, has a human equivalent that could improve understanding of how the infectious airborne disease develops."The findings are encouraging and highlight the role of genetic function in determining whether a person has a high risk of developing tuberculosis," said Igor Kramnik, of the Harvard School of Public Health in Boston, Massachusetts.He and his team, who reported their findings in the science journal Nature on Wednesday, believe the gene SP110 could be a candidate TB-susceptibility gene in humans."The human equivalent may also be involved in innate immunity to the disease and may further lead to development of diagnostic tests and prevention approaches," Kramnik added in a statement.Tuberculosis is a major global health problem with an estimated 8.8 million new cases worldwide in 2003, including 2.3 million in Africa, according to the World Health Organization.Most people with the curable disease spread by coughing and sneezing live in developing countries. TB is a leading cause of death in people with HIV/AIDS.Scientists believe up to a third of the world's population may be infected with the TB bacillus but only about one in 10 people develop active tuberculosis.The researchers said their finding may help unravel the mechanisms involved in developing the illness."Further studies of the Ipr1 gene in a mouse model and its counterpart in humans will improve our understanding of how our immune system works during complex interactions with live, and very successful, pathogens," said Kramnik. (Source: Reuters Health, April 2005)