Major histocompatibility complex individual odors

Source-to-source odor variation in a population of odor-producing objects may be an important statistical feature affecting olfactory perception and behavior. Another recent study showed that variability in the major-histocompatability-complex (MHC) odor signal and the amount of scent marking by individuals affected scent use by female mice when they were selecting mates.They showed that a... 

Schellinck, H.M., Slotnick, B.M. and Brown, R.E. (1997) Odors of individuality originating from the major histocompatibility complex are masked by diet cues in the urine of rats. Anim. Learn. Behav. 25, 193-199. 

In the rat, the major histocompatibility complex (MHC) is responsible for individual odors (Brown etal., 1987a,b). Genetic differences in the JA region actually result in different urine odors (Singh etal., 1987). 

Brown, R.E., Roser, P. and Singh, P.B. (1987 b). Class I and Class II regions of the Major Histocompatibility Complex both contribute to individual odors in congenic inbred strains of rats. Behav. Genet., 79 659-674. 

Overall, these experimental results indicate that (1) urinary odors of individuality in rats and mice are influenced by dietary factors and genetic differences at the major histocompatibility complex (2) the presence of bacteria is necessary for the appropriate expression of both of these cues and (3) methodological factors may influence the outcome of odor discrimination experiments. 

Schellinck, H. M., Monahan, E., Maxson, S. C. Brown, R. E. 1993. A comparison of the contribution of the major histocompatability complex (MHC) and Y chromosomes to the discriminability of individual urine odors of mice by Long-Evans rats. Behav. Genet., 23, 257—263. 

Yamazaki, K., Yamaguchi, M., Boyse, E.A. Thomas, L. 1980. The major histocompatibility complex as a source of odors imparting individuality among mice. In Chemical Signals Vertebrates and Aquatic Invertebrates (Ed. by D. Muller-Schwartz R.M. Silverstein), pp 267—273. New York Plenum. 

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