Every person carries two copies of most genes, with one version, or allele, coming from each parent. Even though these copies tend to be functionally redundant, conventional genetic theory dictates that biallelic expression, wherein both alleles are transcribed equally when the gene is expressed, is nearly universal. But a study published in Cell Reports in January posits something different: that it might be somewhat common for cells to preferentially express only one of a gene’s alleles.
Using a model that characterizes patterns in allele expression from bulk RNA sequencing data, the researchers found that both alleles of some genes were equally active throughout tissues—but for almost 3,000 genes, cells favored one allele or the other, exhibiting what the authors call random allelic expression (RAE). These genes are more likely to acquire harmful mutations, the authors say, and therefore, could act as biomarkers for predicting or diagnosing disease.
Brian Chen, a ...
