Researchers have ascertained that women sniff out men whose body odour is similar to that of their fathers. The theory implies that a man who smells similar to a woman's father is likely to have a compatible immune system.
The natural odours that all humans produce are called pheromones. They are influenced to a degree by a cluster of genes related to the immune system called the Major Histocompatibility Complex (MHC)
50 unmarried women were tested by asking them to smell T-shirts worn by men for two consecutive nights. The US researchers, led by Dr Shirley Bean from the University of Chicago, found that women preferred men with a genetic smell somewhat the same - but not identical - to their own.
Analysis showed a significant correlation with odour components produced by immune system genes inherited from the women's fathers. The scientists suggest that being attracted to some of father's gene smells may be a safe gamble for a woman to ensure her offspring gets a tried and tested immune system.