The study investigates the role of biochemical noise in gene expression variation within genetically identical bacterial populations. The researchers used a single-copy chromosomal gene with an inducible promoter in *Bacillus subtilis* to measure the impact of transcriptional and translational efficiency on phenotypic noise. They found that increased translational efficiency is the primary source of increased phenotypic noise, consistent with a stochastic model where proteins are produced in random bursts. The results provide direct experimental evidence that phenotypic variation in an isogenic population can be regulated by genetic parameters, specifically by increasing translational efficiency. This finding highlights the importance of translation in controlling gene expression noise and suggests that similar mechanisms may apply to naturally occurring genes.The study investigates the role of biochemical noise in gene expression variation within genetically identical bacterial populations. The researchers used a single-copy chromosomal gene with an inducible promoter in *Bacillus subtilis* to measure the impact of transcriptional and translational efficiency on phenotypic noise. They found that increased translational efficiency is the primary source of increased phenotypic noise, consistent with a stochastic model where proteins are produced in random bursts. The results provide direct experimental evidence that phenotypic variation in an isogenic population can be regulated by genetic parameters, specifically by increasing translational efficiency. This finding highlights the importance of translation in controlling gene expression noise and suggests that similar mechanisms may apply to naturally occurring genes.