Behavior Genetics

, Volume 19, Issue 5, pp 659-674

First online:

Class I and class II regions of the major histocompatibility complex both contribute to individual odors in congenic inbred strains of rats

  • Richard E. BrownAffiliated withDepartment of Psychology, Dalhousie University
  • , Bruce RoserAffiliated withCambridge Research Laboratories, Quadrant Research Foundation
  • , Prim B. SinghAffiliated withDepartment of Molecular Embryology, AFRC Institute of Animal Physiology and Genetics Research

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access


The major histocompatibility complex (MHC) of the rat has three regions—A (class I), B/D (class II), and C/E (class I)—and congenic strains are available which differ in each of these regions. We used the habituation-dishabituation procedure to examine the ability of PVG-RT1u male rats to discriminate between the urinary odors of congenic rat strains which differ genetically only at certain individual regions of the MHC. The results of five experiments indicate that discrimination can be made between urine from rats which differ in all three regions of the MHC (PVG vs. PVG-RT1av1 donors), only in the class I A region (PVG vs. PVG.R1 donors), only in the class I C/E region (PVG.R19 vs. PVG-RT1av1 donors), only in the class II B/D region (PVG.R1 vs. PVG.R19 donors), and in all regions except the classical class IA locus (PVG-RT1av1 vs. PVG.R1 donors). These results indicate that all of the MHC regions may contribute to the individual odors of rats.

Key Words

major histocompatibility complex olfaction individual odors habituation chemosensory identification rats Rattus norvegicus congenic strains