Recognition among mice. Evidence from the use of a Y-maze differentially scented by congenic mice of different major histocompatibility types.

Abstract

Previous studies of mating preference signified that mice can sense one another's major histocompatibility complex (MHC) types, probably by olfaction. This conclusion has now been substantiated by the use of a Y-maze whose two arms were differentially scented with currents of air conducted through boxes occupied by B6 (H-2b) males and by B6-H-2k congenic males. Four B6 mice, two males and two females, were successfully trained, by water deprivation and reward, to enter the arm scented by B6 or B6-H-2k males. One of the males and one of the females were trained to select the B6-scented arm; the other male and female were trained to select the B6-H-2k-scented arm. Untrained mice showed no MHC discrimination in the maze. The performance of the trained mice in distinguishing between MHC congenic homozygous F2 segregants derived from a cross of B6-H-2k with B6 was as good as their performance in distinguishing the respective inbred strains, thus essentially eliminating alternative and significant additional explanations of MHC-associated sensory discrimination. The data further indicate that chemosensory discrimination of MHC types can be entirely dissociated from sex differences and from the circumstances of mating.

The evolutionary ecology of the major histocompatibility complex

“…Although the process is not fully understood, MHC genes can affect the concentration of volatile acids that produce odour in sweat or urine (Yamazaki et al, 1979;Singh et al, 1987;Wedekind et al, 1995;Wedekind and Furi, 1997;Hurst et al, 2001;Beauchamp and Yamazaki, 2003;Santos et al, 2004). This could be used as a direct cue to avoid inbreeding, choose particular MHC genotypes or may provide an indication of infection status.…”

In search of the chemical basis for MHC odourtypes

“…While mice can recognize the MHC-driven odour cues from whole body odours, urine and blood (Yamazaki et al 1979(Yamazaki et al , 1999Yamaguchi et al 1981), it has been demonstrated that urine is the strongest and most effective odour source (Yamaguchi et al 1981). Therefore, most chemical investigations have focused on urine-derived compounds.…”

Mouse urinary peptides provide a molecular basis for genotype discrimination by nasal sensory neurons

“…In the first one, the MHC has been considered to influence the volatile composition of urine, as demonstrated by habituation, training and other tests with MHC congenic or mutant inbred strains [9][10][11][12][13][14][15] . Analysis of urinary volatiles of single inbred mice showed considerable variation in the abundance of certain volatiles.…”