Mice help find gene for bad breath

While most cases of bad breath are linked bacteria growing in the mouth, up to 3% of the population have chronic halitosis of no obvious cause.

'It's important to identify the cause of persistent halitosis, and differentiate that cause from relatively benign causes (e.g., gum disease) and the more morbid causes such as liver cirrhosis,' said Professor Kent Lloyd, director of the Mouse Biology Programme at UC Davis.

Researchers at Radboud University in The Netherlands have been studying families with chronic bad breath for several years. They found that these people produced a lot of sulfur-based compounds in their breath, especially methanethiol which has an unpleasant boiled-cabbage smell. Methanethiol is normally produced during digestion but broken down in the body.