Suppose scientists studying pigmentation in arabidopsis attempted to alter expression of a pigment gene. using transgenic techniques, multiple copies of the pigment gene were inserted into homozygous and heterozygous individuals. this was expected to darken the pigmentation of the plants. instead of increased pigment production, the additional gene copies often reduced or completely inhibited the pigment gene expression. one explanation for this unexpected result is that high concentrations of mrna are produced. this, in turn, increases the likelihood of homologous regions of mrna binding with one another and forming double stranded molecules. double stranded rna is often unstable and rapidly degraded by enzymes in the cell. choose a term that describes this mechanism of reduced gene expression.