Humans have fewer coding genes than scientists expected

The number of coding or nuclear genes in human DNA (pictured), the genes involved in the process of making cellular proteins, is much lower than biologists have previously thought. That's according to researchers in an international study coordinated by Spain's National Cancer Research Centre (CNIO), who say the true number of nuclear or coding genes is around 19,000. This is around four thousand fewer than the last estimates.

The researchers worked with data from the three largest reference databases that catalogue cellular proteins and the genes they are based on - GENCODE/Ensembl, RefSeq and UniProtKB - which resulted in a total of 22,210 genes being coded for. However, after a detailed examination, the researchers reclassified 4,234 of them into the non-coding category, often referred to as trash or satellite, which makes up to 75 percent of the human genome. "We have examined many of these genes in minute detail, we are confident," says Michael Tress, one of the CNIO researchers.

The adjustment to the estimate of the number of nuclear genes is not the first, and probably not the last, according to Tress - previously, scientists had talked about as many as 100,000 genes, but other estimates have lowered that figure to between 20,000 and 24,000. Some studies have even talked of as few as 18,000 coding genes. But the current figure is said to be around 19,000. "Even if only half of the genes we have identified are confirmed to be non-coding, this will have a significant impact on many research and medical disciplines," the authors conclude on the CNIO website.

Source: https://www.e15.cz/magazin/clovek-ma-mene-kodujicich-genu-nez-vedci-cekali-1350800