It is doubtful that monkeys would have evolved to walk on two legs millions of years ago, freeing up two hands for humans to use tools. So bipedal locomotion, or walking on two legs, might be considered one of the most significant breakthroughs in human evolution. Scientists now claim to have discovered the gene responsible for this.

According to Columbia University, researchers used deep learning and genome-wide association analyses to build the first map of the genomic areas responsible for the skeletal alterations in primates that led to upright walking. This map demonstrates that the genes responsible for these alterations were highly supported by natural selection, providing early humans and evolutionary advantage.

“On a more practical level, we’ve also identified genetic variants and skeletal features that are associated with hip, knee, and back arthritis, the leading causes of adult disability in the United States,” Tarjinder Singh, co-author of a study published in the journal Science, says in a press release.

The researchers examined over 30,000 full-body X-rays from the UK Biobank for the study and developed a deep learning algorithm to standardise the X-rays, reduce quality concerns, and correctly assess several bone parameters.

They next searched the human genome for chromosomal areas associated with differences in 23 major skeletal measurements. Shoulder breadth, torso length, and tibia-to-femur angle, for example. This study discovered 145 areas linked to genes that control skeletal growth.

They discovered that many of these 145 regions overlapped with “accelerated regions” of the human genome, which evolved at a much faster rate than the identical regions in giant apes.

“What we’re seeing is the first genomic evidence that there was selective pressure on genetic variants that affect skeletal proportions, enabling a transition from knuckle-based walking to bipedalism,” said co-author Vagheesh M Narasimhan in a press statement.

Categorized in: