The Genes that make us ill

We might become sick from the genes that made us fully human

0
76
The Genes that make us ill
Genes that make humans, make human ill too

Introduction

Our ancestors diverged from our nearest living relatives, the chimpanzee and other great apes. By acquiring the genetic mutations that ultimately led to the development of the human species. Our predecessors’ brains doubled in size, providing greater behavioural flexibility. Alterations to the tongue and vocal cords contributed to the creation of human speech and language. The skeletal, muscular, and joint adaptations that ancient humans underwent enabled them to traverse across great distances, walk erect, and hold and launch projectile weapons.

Bipedalism

Bipedalism is among the first things that come to mind when considering what it means to be human. Our ancestors had an edge since they could walk upright on two legs. Allowed them to carry food, use tools, and hunt animals over great distances. Walking on two legs was a rather quick for humans after they split from chimpanzees’ last common ancestor. Humans were fully bipedal by the time Homo erectus lived in East Africa 1.9 million years ago. Nevertheless, before our ancestors could walk on two legs. They had to undergo some changes in the knee. Compared to chimps. Humans have thicker knees because they have many more bony surfaces and cartilages to support them.

Because chimpanzees are knuckle walkers and cannot balance on two legs, their knee joints are entirely different from ours, according to Harvard University professor of human evolutionary biology Terence D. Capellini.

A 2020 Study

The knee is so vital to humans, the genome ought to contain evidence of its evolutionary history. His group used cartilage cells from growing mouse and human embryos in a 2020 study. When the knee is starting to take shape and develop. Subsequently, they sequenced the cells’ DNA in an attempt to find “human accelerated regions” (Hars). Hars are regions of the genome where the sequence in humans is substantially different from that in chimpanzees, orangutans, and other primates, but it is exactly the same or very similar in these animals. Stated differently, these are useful sites for searching for “the genes that made us human”.

A study discovered a large number of Hars in the regulatory switches that govern the biology and shape of the growing knee. Regulatory switches govern the expression of other genes rather than directly coding for proteins themselves.

DNA of Cells

They also sequenced the DNA of cells from other developing skeletal regions, like the elbow, ankle, and shoulder, as a control. In these areas, there were much less Hars. This suggests that, in opposite to switches controlling other parts of the skeleton, those controlling the morphology of the knee underwent rapid evolution in humans. But it appears that the switches stopped evolving quickly following this evolutionary spurt. Capellini found less genetic variation in these “knee shape switches” when examining the genomes of living humans. That makes sense—our ancestor’s ability to walk depended heavily on having a functioning knee.

Bigger Brains

Rapid evolutionary changes in humans have resulted in larger brains with more neurons dedicated to the outer cerebral cortex. The region involved in higher order cognitive functioning. In fact, in the six million years that have passed since Homo sapiens and chimpanzees last shared an ancestor. The size of the human brain has roughly doubled. However, new research shows that many of the genetic changes that made these changes possible are now linked to conditions including autism and schizophrenia. For instance, two study teams in 2018 discovered the Notch2NL gene family, which may have been a major factor in the creation of our huge brains and appears to be vital for human cortex development.

Synapses

The quantity of synapses, or connections, that a neuron forms with nearby cells is mostly regulated by genes. A neuron can process more information the more synapses it has. Humans are essentially able to generate more synapses and stronger, denser connections between neurons because to the newly discovered, human-specific SRGAP2C gene.

Gene duplications like those that resulted in SRGAP2C and Notch2NL may have made us susceptible to neuropsychiatric illnesses, even though they may explain why our species is so smart. For example, mutations in the Notch2NL-encoding region of the genome have been linked to a variety of neurodevelopmental diseases, such as intellectual disability, ADHD, schizophrenia, and autism spectrum disorder.

Conclusion

Our ability to alter and modify our surroundings has allowed us to act far faster than evolution has been able to keep up. An evolutionary mismatch could result from this, making adaptations that have evolved over tens of thousands of years unfit for our contemporary lifestyle. Comprehending the ways in which specific genes cause diseases may serve as an inspiration for novel therapeutic approaches. According to others, it may even take part to the development of a new era of precision medicine, when specific medications are prescribed based on each individual own genetic profile. Some, though, use greater caution.

 

 

 

 

 

The MYI News World is source for the latest news, blogs, articles, job updates, and a wealth of valuable information. We recognize your need for access to current, clear, and reader friendly content, and that’s precisely what MYI News World provides.

LEAVE A REPLY

Please enter your comment!
Please enter your name here