Do Stem Cells Hold the Answer to Understanding the Evolution of Man?
One of the biggest questions in the world of science is how the human body developed.
Stem cells, or cells with the ability to develop into many types of cells, have given scientists the ability to come closer to answering this question by allowing researchers to focus on specific parts of the human body.
For example, in Germany, scientists have been able to grow ‘mini-brains’ from human stem cells to focus on the Neanderthal DNA in the cells.
From this research, scientists from the Max Planck Institute for Evolutionary Anthropology hope to further understand and track the relationship between Neanderthals and modern humans and establish which aspects of modern humans are similar to traits of Neanderthals.
Researchers obtained stem cells from the Human Induced Pluripotent Stem Cells Initiative, a program that provides human stem cells for research.
The Human Induced Pluripotent Stem Cells Initiative, or “HipSci,” provided the research team with stem cells coming from individuals of European descent.
Past studies have shown that about one to four percent of the genome of a European individual is composed of Neanderthal DNA, explaining how Neanderthal DNA can be studied within human stem cells.
This implies that a proportion of human alleles, or different forms of genes, are shared with Neanderthals. Therefore, by using stem cells of European descent, researchers are able to establish and further study the relationship between Neanderthals and modern humans.
Using the stem cells obtained from HipSci, scientists grew “organoids” that resembled brain tissue.
Growing organoids allowed researchers to mimic human organs outside of the body, creating a safe environment to analyze the Neanderthal DNA.
Using RNA sequencing to study the cell composition of the organoids, enough data was obtained to confirm that it is possible to track the Neanderthal RNA across different developmental processes.
This confirmation for tracking Neanderthal RNA implies that there is a newfound ability to assess and further understand the origins of human development.
Scientists wish to further develop their research by scaling up the number of stem cells used in the experiment.
With the organoid’s capability to recreate other areas of the modern human body, scientists are hoping to further investigate the effects of Neanderthal DNA on different developmental processes and phenotypes.
Such areas include the “intestinal tract and digestion, cognition and neural function, and the immune response to pathogens” (Randall).
In the future, researchers believe there is a possibility that the idea of tracking the origin of traits from shared ancestors can similarly be implemented with other ancient human populations.
By studying other ancient human populations, the development of human traits, researchers will be able to have a more well-rounded understanding of where each human trait originated.
With this research and the impressive utility of stem cells, scientists are closer than ever to understanding the origins of different aspects of the human body.
Written by Zachary Ostrow
Edited by Rohan Mehta, Jason Kauppila, Jared Nussbaum, Calvin Ma, Shaw Rhinelander and Alexander Fleiss