That means people are able to sniff out suitable MHC genomes in prospective partners.

ECONOMIST: Perfume science

The correlation is with the genes of what is known as the major histocompatibility complex (MHC).

ECONOMIST: Perfume science

Dr Milinski and Dr Wedekind also found an association between a woman's MHC genes and some of her preferences for perfume.

ECONOMIST: Perfume science

The MHC is also thought to act as a proxy for general outbreeding, with all the hybrid vigour that can bring.

ECONOMIST: Perfume science

You might, though, have better luck choosing for a close relation, because she would probably have an MHC similar to your own.

ECONOMIST: Perfume science

Fortunately, then, evolution has equipped mammals with the ability to detect by smell chemicals whose concentrations vary with differences in the MHC of the producer.

ECONOMIST: Perfume science

Perception of musk, rose and cardamom is correlated with the MHC.

ECONOMIST: Perfume science

It turns out that one of the most important aspects of mate choice in mammals, humans included, is to make sure that your mate's MHC is different from your own.

ECONOMIST: Perfume science

Women, it seems, choose not the kind of smell they would like on a partner, or even one that might mask a nasty odour of their own, but rather something that matches their MHC.

ECONOMIST: Perfume science

If you have made a good genetic choice of partner (ie, someone with a significantly different MHC), then the theory suggests that you should not be able to choose something that smells nice to them based on your own preferences.

ECONOMIST: Perfume science

MHC, helps to determine body odour.

ECONOMIST: Cor, you don��t half smell