Anyone’s height is greatly affected by their DNA and scientists are turning to the gene variant that affects this trait.
Antonio_Daz / East St c
By Jocelyn Kaiser
For height, DNA is largely destiny. Studies of identical and fraternal twins suggest that as much as 80% of the difference in height is genetic. But the responsible genes have largely excluded researchers. Now, by collecting genome data for 4 million people, which is by far the largest study – geneticists have considered a large part of this “missing heritage”, at least for people of European descent. In this group, they have identified about 10,000 DNA markers that fully explain the influence of common genetic types on altitude.
“This is a real milestone,” says Daniel McArthur, of the Garvin Institute of Medical Research in Australia. ‘
Luck Yango of the University of Queensland in St. Lucia, Australia, suggests that, if extended to other genetic contributors and other ancestors missing in other qualities and diseases, the results will “inform new biologists and contribute to individual medicine”. The team presented the online work this week at the annual meeting of the American Society for Human Genetics. For example, geneticists can more accurately assess people’s risk of disease with a genome scan. But the study is unsatisfactory to some scientists, as it identifies markers associated with genes that fly at heights, not just genes.
The mystery of missing inheritance dates back to the late 2000s, when researchers began using new tools to scan the human genome for common markers associated with diseases and symptoms. They expect that the results of this Genomewide Association (GWA) study will match evidence of genetic predisposition to twins and families, such as the overwhelming influence of genes on height in rich countries, rather than diet or environmental factors such as childhood infections.
But it turned out that each identified marker, which may be in or close to the respective gene, contributes little to the risk of a symptom or disease, and compromising them does not solve the problem. For height height, the first 40 DNA markers attached to the trait explained only 5% of its difference.
Numerous possible revelations emerged that the GWA study, including rare gene variants lost through gene-to-gene interactions, and the twin studies were incorrect. But Yango’s team leader Peter Wisker argued that it was a partial matter to find many common types with very little impact. He estimated that such species should account for 40% to 50% of the genetic component of height. However, it is necessary to study the DNA of a large number of people to rule out vague signals.
By 2018, Wischer’s team and other members of a global consortium called GIANT pooled DNA data for 700,000 people and found 3,300 common markers that explain the 25% ation altitude difference. Now, looking at DNA from a 201 GWA study with 4.1 million participants, GINT has brought in a total of about 9900 common markers, a difference of 40%. Other markers located nearby and possibly inherited hold another 10% of the height currency.
That is still less than the 80% predicted by the two studies. But last year, Wischer’s group, based on full genome sequencing data from a small number of people, pointed out that rare types performed by less than one in 100 people would explain the 30% difference in height. (The result was revealed in the March 2019 print edition that the team is improving.)
Some geneticists say they are not surprised that once enough people scan their DNA, the gap in inheritance can be filled. “It was expected,” says Arvinda Chakraborty of New York University. The problem has been that some DNA markers linked to a few heights have been linked to specific genes that clearly alter the trait. “It’s almost all‘ missing ’in the biological sense,” says David Goldstein of Columbia University.
The new findings make the chances of finding those genes brighter, Yango says. Rather than randomly scattering over the entire genome, gaining control over specific genes and their roles will always be challenging, with 9900 or more markers limited to only about 30% of the genome. And many clusters in the field containing the genes involved in growth.
