HISTOLOGY AND WEIGHT OF THE MOUSE ADRENAL: A DIALLEL GENETIC STUDY

Abstract
SUMMARY: Relative adrenal weights were obtained and histological preparations of the adrenals were made from adult offspring derived from all mating combinations of four pure strains of mice. Both quantitative and qualitative genetic differences in the adrenals were found. The following variables affecting adrenal weight were significant: laterality, sex, strain, gametes, reciprocals, and reciprocals by sex (sex-linkage). Histological investigation of the adrenal glands of females aged 100 days differed in the absence or presence of heritable peri-medullary fatty metamorphosis of cortical cells. X-zone degeneration was independent of laterality and was found in two pure strains including all hybrid combinations of the two and a third strain. Females from genotypes displaying X-zone degeneration had significantly heavier adrenal glands than the remaining groups. The results of this diallel study indicate the presence of systematic genetic influences underlying histological and morphological differences in the mouse adrenal.