The findings relate to the genetics of modern Pima Indians who have an unusually high rate of obesity but could be extrapolated to all people. Their obesity is thought to be linked to a thrifty metabolism that allowed them to metabolize food more efficiently in times when little was available but causes problems when food is in abundance.
Mark Rowe, David McClellan, and colleagues at Brigham Young University in Provo, Utah, USA, have studied the effect of evolutionary selection on Pima Indians, a people indigenous to the present-day Sonora desert of Arizona and New Mexico. The researchers anticipated an effect consistent with higher metabolic efficiency among these people and focused specifically on recently discovered variations in their mitochondrial DNA, so-called SNPs, or single nucleotide polymorphisms.
The metabolic rates of 200 obese Pima individuals were measured and revealed that two of the three known SNPs influence metabolic efficiency. The researchers then used the genetics software TreeSAAP, to analyse the biochemical changes caused by these SNPs and then tracked the evolutionary selection of these genetic variations in 107 different types of mammals. This allowed them to propose a mechanism by which these SNPs affect the mitochondrial respiratory chain and consequently increase metabolic efficiency in the Pima people.
The team suggests that an increased metabolic efficiency could have been an evolutionary advantage. The SNPs may have persisted because they helped the Pima survive the harsh dietary environment of the Sonora desert throughout the history of the people. In the current environment of caloric over-consumption an increased efficiency is unfavourable and may contribute to the high rates of obesity among the Pimas.
While the Pima Indians are an extreme case, the entire human population may also have evolved in a restricted caloric environment, say the researchers. Many populations may exhibit similar SNPs that were advantageous to our ancestors but may now be detrimental. The presence of these SNPs may thus provide one explanation as to why obesity is so rife in the 21st century.
Jim Corlett | alfa
Climate Impact Research in Hannover: Small Plants against Large Waves
17.08.2018 | Leibniz Universität Hannover
First transcription atlas of all wheat genes expands prospects for research and cultivation
17.08.2018 | Leibniz-Institut für Pflanzengenetik und Kulturpflanzenforschung
New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference
Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...
Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.
Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...
17.08.2018 | Event News
08.08.2018 | Event News
27.07.2018 | Event News
17.08.2018 | Physics and Astronomy
17.08.2018 | Information Technology
17.08.2018 | Life Sciences