Odortypes: Their origin and composition

Odors that distinguish one individual from another member of the species and are determined by polymorphic genes are called odortypes. Odortypes and their considerable societal significance have been studied intimately only in mice and mainly with respect to the genes of the major histocompatibility complex. Further understanding and the matter of human relevance have been hampered by the apparent restriction of odortype expression to urine. The present finding that odorants comprising prerenal odortypes are already present in blood, albeit in masked form, affords the basis of a comprehensive view of odortypes. Accordingly, major histocompatibility complex and other polymorphic genes of antiquity are seen inter alia as agents of normal variation, which entails quantitative variation in output of odorant metabolites. Relatively few such normal variations should suffice for a vast range of compound odors whose specificity is determined by combinative assortment of the same set of individual volatile compounds.

由多态性基因编码、可区分物种内不同个体的气味，被称为个体气味型（odortype）。个体气味型及其显著的社会意义，目前仅在小鼠中得到了深入研究，且主要围绕主要组织相容性复合体（major histocompatibility complex, MHC）的相关基因展开。此前，由于个体气味型的表达似乎仅局限于尿液中，对其的进一步研究以及探讨其与人类的相关性均受到了阻碍。本研究发现，构成肾前个体气味型的气味物质已存在于血液中，尽管其处于掩蔽状态，这为全面解析个体气味型奠定了基础。据此，主要组织相容性复合体及其他古老的多态性基因，除其他功能外，可被视为正常变异的介导因子，这类变异会导致气味代谢物产出的数量差异。此类正常变异的数量相对较少，却足以产生种类极其丰富的复合气味，其特异性由同一组单一挥发性化合物的组合搭配所决定。