For a long time, gene expression seemed straightforward. We knew that when cellular machinery reads an active gene, it gets transcribed into mRNA and then modified before being translated into protein. But research has shown that sometimes, there’s “misbehavior” in gene expression. For example, transcripts may not always start or end where they should. And new research shows that occasionally, genes are active even when they shouldn’t be, even in healthy people.
A study reported in the American Journal of Human Genetics described several situations where inactive genes are expressed anyway. The study found that misexpression is rare at the level of single genes but can occur in over half of genes that should not be expressed in healthy people. This work may help explain how complex disorders involving many genes arise.
There are around 20,000 genes in the human genome that code for proteins. The identity of specific cells largely depends on which genes are expressed. Thus, gene expression has to be carefully controlled or problems can arise. While there are some rare disorders known to involve gene misexpression, this study is one of the first to investigate it in healthy people.
The researchers analyzed blood samples from over 4,500 healthy people and found that while only a small percentage of genes showed misexpression, almost every sample had evidence of it (96 percent). Most misexpression was due to structural changes in DNA, which can affect gene expression.
These results suggest that many healthy people do misexpress some genes, but at low levels and probably doesn’t have a major impact on health. However, there may be cases where misexpressed genes exert a serious influence.
Source: https://www.labroots.com/trending/genetics-and-genomics/27505/gene-misbehavior-surprisingly-common-healthy-people