Can Molecular Imprinting Explain Heterozygote Deficiency and Hybrid Vigor?
R. Chakraborty Center for Demographic and Population Genetics, The University of Texas Graduate School of Biomedical Sciences, Houston, Texas 77225 Molecular imprinting, the phenomenon of differential expressions of a gene based on whether it is paternally or maternally derived, has been noted in mice, humans, and other nonmammalian organisms. Effects of differential imprinting are important not only in the study of the manifestation of deleterious genes; they have important evolutionary implications as well. It is shown here that molecular imprinting may mimic observations that are often construed to be due to hybrid vigor and/or inbreeding depression. Furthermore, if a locus undergoes differential imprinting, it also yields observed genotypic proportions which mimic heterozygote deficiency in the population without the aid of natural selection.
