Developmental stability is the ability of organisms to buffer against the random variation that arises spontaneously as a consequence of stochastic variation in the cellular processes that are involved in the development of morphological structures. Its converse, developmental instability, is...

There is growing genomic evidence on clustering of functionally related genes in eukaryotes. Recent studies in yeast show a correlation between the expression patterns of adjacent and nonadjacent pairs of genes and that a significant proportion of the former are functionally related. A...

Butterfly color patterns are built as finely tiles mosaics of colored scales, each the product of a single epidermal cell. The overall pattern is composed of a small number of pigments. Each scale appears to make an all-or-none “choice” to synthesize only one of this small set of...

This chapter addresses the abyss that currently exists between quantitative genetics theory and regulatory biology. My claim is that despite the apparent success of quantiative genetics within evolutionary biology and production biology, the conceptual and methodological foundation of the theory...

Recent evidence from a variety of studies has indicated that gene regulatory mechanisms in multicellular eukaryotes operate in a dosage dependent manner. A consequence of this fact is that new mutations in regulatory loci are available for adaptive selection in the heterozygous state, which is...

Dominance is the masking at the level of the phenotype of the presence of one of the two alleles at a diploid locus. We discuss whether it could be an automatic consequence of cellular physiology, as proposed initially by Wright and elaborated by Kacser and Burns, or whether it might be a...

Growing evidence suggests that genes are not expressed at steady state levels, but instead, gene transcription has a stochastic component. We review recent literature concerning stochastic gene expression and discuss our model in which allele copy number influenced the probability that the...

Here we explore the phenomenological and mechanistic bases of dominance. Dominance can be defined as an operational measure of the deviation of the heterozygote’s observed trait value from its expected value based on the phenotype of the two homozygotes. A simple mathematical analysis of...

We describe simple mathematical models of gene expression to explore the possible origins of haploinsufficiency (HI). In a diploid organism, each gene exists in two copies and when one of these is mutated, the amount of proteins synthesized is reduced and may fall below a threshold level for the...

I review recent findings from the stoichiometric analysis of metabolic networks. These findings show that the physiological theory of dominance, which explains dominance in metabolic genes from kinetic properties of biochemical pathways and redundant allelic functions is incomplete....