Uncovering the Genes That Let Our Ancestors Walk Upright

        Charles Darwin is widely known for developing ideas of evolution by natural selection, and he extended his ideas in relation to humans in his book. He released "The Descent of Man", in 1871, where he argued the cause of humans evolving from our ancestors, the ape. He argued one of the biggest changes being upright walking in humans. This bipedalism is now known as one of the most defining characteristics of humanity.

    However, since Darwin's monumental discovery, there's been some more breakthroughs in how exactly this happened on a molecular level. It was hypothesized that it was not because new genes arose, but because old genes began doing new things, meaning some genes became active in humans.

                   Comparison of skeletons from "Evidence as to Man's Place in nature," by Thomas Henry Huxley, 1863.

    A key feature to humans walking upright is the ilium bone. The bone is responsible for walking, supporting organs, and childbirth. The bone is fused to the base of the spine, goes around the waist, and in front of the belly. The development of the ilium is a mystery still though, very little is known about its origin. After much in depth research on 18 different primate species, it has been found that in human embryos, the ilium begins as a single rod that forms perpendicular to the spine. But for most species studied, the ilium begins as two cartilage rods parallel to the spine. Humans have the same gene to form the bone, but in humans it activates in a different manner. This change in bone structure is what has allowed for humans to develop a pelvis that is strong enough and suitable for bipedalism. 

    Another discovery involved a second evolutionary change, being that the ilium turns from cartilage to bone much later than the rest of the human skeleton, by about 15 weeks. It is hypothesized that this evolved about 1 million years ago following the growth of the human brain, which required a larger birth canal to support the larger babies' heads.

    This discovery about the origin of bipedalism in humans is a huge milestone in the understanding of human evolution. It is so awesome that it was seen that the same gene in humans was also found in other apes, but those same genes became active in new ways that led to bipedalism in humans.

References:

Wobser, A. M. (2023, July 24). Anatomy, abdomen and pelvis: Bones (ilium, ischium, and pubis). StatPearls [Internet]. https://www.ncbi.nlm.nih.gov/books/NBK519524/

Zimmer, C. (2025, August 27). Uncovering the genes that let our ancestors walk upright - The New York Times. https://www.nytimes.com/2025/08/27/science/human-evolution-ilium-bipedal.html

A Genetic Finding Suggests Mutation to Make Horses More Rideable

        The modern domestication of horses can be dated back to over 4,200 years ago. A team of scientists, led by molecular archaeologist Ludovic Orlando, observed the genomes of ancient horses and compared them to ones of the domesticated horses humans are familiar with today. Whilst studying the genomes, nine specific genes stood out as selected and targeted by human breeders   

 

        One gene recorded was ZFPM1, a gene familiar to scientists as the marker for anxiety levels in mice and human well being. This was one of the first genes selected by breeders around 5,000 years ago, suggesting the original concern for domestication was keeping the horse tamer.

        Interestingly enough, around 300-800 years later, the breeders advanced their selection and the gene Gasdermin C (GSDMC) strongly started to appear. In humans, a mutation of this gene causes chronic back pain and disorders such as spinal stenosis. In horses, it is seen to be related to the body length to body height ratio. 

        Once Orlando and his team discovered horses with this gene mutation when first appearing had 20% more offspring than those without, they ran testing on mice and inactivated their GSDMC genes. This experiment found the mice's spines modified to become straighter and forelimbs to be stronger.

        Orlando concludes "people intended to put that variant more frequently into the population... when you see something like that, you know you're onto something that was a real game changer for horse biology".

        The research done by Orlando and his colleagues is impressive and presents the importance of to be able to fully understand the human selected genes of any animal, in this case horses, it must be compared to the original non-domesticated ancestor. Learning more about the genetic makeup of one of the first animals domesticated by humans can help us further learn about the scientific thought process of our ancestors. 

Sources:

https://www.sciencenews.org/article/tamed-horses-rideable-genetic-mutation 

https://www.ncbi.nlm.nih.gov/gene?Db=gene&Cmd=DetailsSearch&Term=56169 

                   

New Study Reveals Shared Genetic Markers Underlying Substance Use Disorders

 

     Scientists have identified genes that are commonly inherited across addiction disorders, regardless of what substance was used. The study was led by researchers at the Washington University in St. Louis. In 2021, more than 46 million people in the U.S., at the age of 12 or older, had at least one substance use disorder, with only 6.3% receiving treatment. About 107,000 people died of drug overdoses in 2021, with 37% of the deaths involving opioid and stimulant drug exposure. Disorders caused by substance use are heritable and influenced by interactions among different genes and environmental factors. The genome-wide association is a method that searches entire genomes for regions of genetic variation, called single-nucleotide polymorphisms, that associate with the same disease or condition among multiple people. In the study, researchers used this method to identify areas in the genome that were associated with general addiction risk and risk of substance specific disorders. A sample of 1,025,550 individuals with genes indicating European ancestry was used and so was a sample of 92,630 people with genes indicating African ancestry. The research team discovered various molecular patterns, including 19 independent SNPs associated with general addiction risk and 47 SNPs associated with substance specific disorders. These identified patterns were among the European ancestry. The strongest gene signals that were consistent across the different disorders were located in areas of the genome responsible for regulation of dopamine signaling, indicating that dopamine signaling regulation is an important part of addiction risk. The genomic pattern associated with general addiction risk predicted higher risk of mental and physical illness, including suicidal behaviors, chronic pain conditions, psychiatric disorders, and respiratory conditions. In children aged 9 to 10 years old, the presence of these genes correlated with parental substance use. Genomic analysis in the African ancestry sample showed one SNP associated with general addiction risk and one SNP associated with alcohol use disorder. 

This research is very intriguing. Firstly, it’s intriguing in that the results between the different ancestries are drastically different. It could also be taken into account the different sample sizes between the two ancestries. However, due to the sample sizes and the limited research done so far, the data cannot be used to categorize genetic risks within certain populations. But, including populations that have historically been underrepresented in biological and biomedical research could lead to a better accuracy in the found results. Hopefully, this research opens a pathway to discovering the factors that protect or predispose a person to a substance use disorder. Through these findings, the hope is that new treatments and preventative measures could be found against multiple substance use disorders

https://nida.nih.gov/news-events/news-releases/2023/03/new-nih-study-reveals-shared-genetic-markers-underlying-substance-use-disorders 

https://www.nimh.nih.gov/health/topics/substance-use-and-mental-health

A New Look At CRISPR

    Recently there have been significant advances in CRISPR gene-editing technology. The CRISPER stands for "Clustered Regularly Interspaced Short Palindromic Repeats" which refers to a family of DNA sequences that are found in genomes of bacteria and other microorganisms. 

   

 In recent news, researchers apart of Harvard University, Broad Institute, and the Howard Hughes Medical Institute have found advances in the CRISPR gene. Two papers were published with the work and the finding. The first paper deals with the introduction of cytosine base editors. These cytosine base editors reduce off targeting and edit by a 10 to 100-fold, and this is showing for treatment in human diseases. 

    The second paper deals with the new finding of CRISPR-Cas9 proteins and how they are capable of targeting larger fractions of pathogenic mutations like the ones that are responsible for diseases related to sickle cell anemia. With these findings are also advancements which are trying to minimize risks of adverse effects and start to expand the components of CRISPR in genome editing. In the research it showed how CRISPR has limited ability to access the entire human genome and introducing us to proteins which are able to recognize DNA sequences without a common pattern. This allows us to target half of DNA sites, even those that were challenged mutations. Because of these findings we have been introduced to more ways to edit genomes and find treatments for genetic diseases.

Source:

How CRISPR technology is advancing — Harvard Gazette

Other:

What is CRISPR/Cas9? - PMC (nih.gov)

Enormous fern genome

  

"Strange Tree Fern Has a Surprisingly Enormous Genome", ferns reproduce similarly to mushrooms by releasing clouds of spore and split from seed baring plants millions of years ago. Fern genomes are very large and were just fully sequenced fairly recently. A large genome genome adds opportunities for advantageous mutations that buffer from undesirable ones. Researches found which genes build the ferns trunk-like stem and provided insight on how key traits evolved in stemmed plants. In addition, in the article, "Scientists Sequence Genome of Flying Spider-Monkey Tree Fern", it is discussed how knowing their genomes and how tree fern species are being overexploited in combination with climate change and threatens their survival. Not only did they just fully sequence their genome they used biochemical methods to measure the levels of lignin and secondary metabolites. 

Sequencing species genomes is important to linking other species and finding their relatedness. Not only does knowing their genomes allow for further research it allows us to determine hereditarily from the ancient plants. 

Short Lived DNA Loops

This article discusses the findings of a study from MIT which suggests that loops formed from proteins coating DNA are more short lived than previously thought. The researchers monitored the movement of one stretch of the genome in a living cell for about two hours. 

These loops are formed by a process called extrusion. This is when a molecular motor promotes growth of larger loops. These experiments during this study only offered snapshots of moments in time, and offered very little information about how loops change over time.

The researchers used this method to see the stretch of the genome in mouse embryonic stem cells. If the loop was present for a 20 to 45 minutes out of the entire duration of cell division which is about 12 hours, then this fully looped state is not the primary regulator of gene expression. One of the researchers recommended that new models of DNA repair, 3D structure of the genome, and other processes are necessary. They argue that the process of extrusion is more important than having loops that are constantly extruded. 

Because other loops in the genome are more difficult to study, they plan to study these loops in a variety of different cell types. This technique could offer an abundance of information about the ways in which the short span of these loops could potentially affect gene expression. There are thousands of loops and these MIT researchers only examined one during this study. There is also a relationship between the neurodevelopmental disorder FOXG1 syndrome and faulty loop formations. Using the same technique that was used during the study will allow the researchers to look at other loops. Here is a similar article. 

Parents Test Their Children's DNA in China

https://www.technologyreview.com/s/612976/china-parents-genetic-testing-for-kids-talent/
Related article:
https://www.livemint.com/news/world/chinese-parents-test-dna-to-see-if-kids-will-be-smart-11574266331105.html

In China, there are clinics that are opening in cities that claim they can find children’s talents within their DNA. These clinics claim to test traits such as musical, mathematical, and reading abilities, physical talents, introversion, extroversion, and memory. Although there is not much science behind these tests for accuracy, “talent testing” contributes a lot to China’s fast-growing genetics industry. Several clinics claim that they get about 100 to 200 parents testing their children’s DNA each week. Most parents that do the "talent testing" want to know what their children's abilities are so that they could become prodigies in that specific area instead of making their child/children pursue things that they are not necessarily good at.

I'm curious as to what other people think about these parents paying thousands to get their children “talent tested” with almost zero science backing the accuracy of these tests. I appreciate the intentions of these parents, I like how they want their children to succeed in areas they are good at and to pursue their natural-born talents, but I personally do not think it is worth it. I do not think it is worth it because there are still no scientific explanations for the relations between the genome and a lot of traits. I also am not fond of the idea of already knowing what your child is good at through a genetic “talent test”. If I were a parent I would want to learn along with my child through experience what his or her talents are instead of knowing everything right off of the bat. This article also sparked my curiosity about the future, if these tests become global and easily accessible by anyone once there is more scientific explanation for them, how will our society react to them?

Genetic Links associated with Schizophrenia Discovered

Professor Sir Mike Owen, at the MRC Centre for Neuropsychiatric Genetics and Genomics at Cardiff University have found more than fifty new genes that may increase your risk of developing schizophrenia. In a study, titled, “Common Schizophrenia alleles are enriches in mutation-intolerant genes and in regions under strong background selection,” conducted using more than one-hundred thousand individuals, and of those forty-thousand with diagnosed schizophrenia, genes associated with the development of schizophrenia and other neurodevelopment diseases, such as autism, have been isolated.

From this experiment, a major link between the genes associated with schizophrenia and the genes dealing with development has been discovered. If your genes associated with development are compromised, then your risk for developing schizophrenia is increased. For the first time, it is understood that the mutation of these fifty genes can increase your risk for development schizophrenia. In addition, an important question was answered: “if people with schizophrenia have, on average, fewer children than people without the disorder, why does schizophrenia still affect so many people?” The answer is that the genes affiliated with the mental disorder occur in a good majority of the population, and the area, on the genome, where these genes reside, is where natural selection is not very effective. With that, these genes have yet to disappear from the genome, which is why people are still affected by schizophrenia.

This study will be furthered, but, for now, has opened the door for many new treatment options. By understanding the complexity and genetics behind schizophrenia, personalized treatment options may be available, in the future. With better treatment options, those suffering from the schizophrenia will be able to live a better life, without worrying about their illness.

Article: https://www.sciencedaily.com/releases/2018/02/180227111701.htm

Image: http://assets1.bigthink.com/system/idea_thumbnails/51344/size_1024/brain_sketch.jpg?1372009404

How Did Insects Get Their Wings?

Insects were the first organisms on the planet to have the ability to exploit particular environments to aid in their survival. It has been a mystery on to how these creatures developed their ability to fly and there has long been two hypothesis onto how wings came about. The "tergal hypothesis," suggests that the wings developed from the top of the insect body wall and formed gliding membranes while the, "pleural hypothesis," suggests that wings developed from ancient leg segments that originally merged with the body before ending up on the back. Now with the advancing developments in evolutionary biology, researchers are now suggesting a, "dual origin," hypothesis where wings fused from two separate tissues: the dorsal body wall and leg segments.

Dr. Tomoyasu and David Linz, two researchers, recently published in the National Academy of Sciences, were able to genetically engineer beetle larvae with an additional pair of wings on their abdomens. By injecting green fluorescent proteins into beetle larvae they were able to mark genes that expressed wing development. With these particular genes exploited, the researchers were then able to develop larvae with an additional set of wings on their abdomen. This result may suggest that insects may have originally had three sets of wings and lost a pair due to the possible loss in aerodynamics throughout natural selection. However, this data is just a fraction on what is needed to confirm how insects truly gained their ability to fly.

Article: https://www.nytimes.com/2018/03/26/science/insect-wing-evolution.html
Original Paper: http://www.pnas.org/content/early/2018/01/08/1711128115

DNA Helps in Immune Cells Development

If immune system of human beings is not working or developed properly enough many diseases impact our health. According to the article on medicalxpress, for the immune system to develop properly, it needs the right information at the right time: genetic components have to be activated at the precise time, and promoter areas must be paired exactly with the enhancer clusters. Promoter area is where the gene is expressed, and enhancer clusters are where the cells are matured to perform their specific functions. If the things mentioned above do not happen in a synchronized manner diseases like leukemia result.
The article further explains that the part of DNA known as the non-coding DNA plays a huge part in bringing promoter and enhancer regions together with utmost accuracy by changing the 3D structure of the DNA.When the shape changes, the two regions are brought close together in a loop.  After that, both are separated and repositioned to begin the development of T-cells, which are also known as the building block of the immune system. Hence; the DNA helps the enhancer and promoter regions to find each other at the right time, which results in maturation of immune cells. I have always been mesmerized by the DNA, and to know that it also helps in the development of T-cells is truly astonishing. As mentioned in the article, I hope this discovery will lead to the development of many new treatment methods like treating mutations and suppressing tumors.

Ancient skeletons show direct link to modern tribes in the Pacific Northwest

Ancient skeletons show direct link to modern tribes in the Pacific Northwest    

After 21 years of a group of archeologist and anthropologist working together to uncover the true decedents of the Native American tribes in the Pacific North, a team of geneticists were able to extract nuclear DNA form a 10,300-year-old skeleton named Shuka Kaa who could shed some light on the lineages of these natives. The Native Americans who reside in the Pacific Northwest claim to have what they call “deep roots” to the region, being there from the very beginning before anyone else, and now new genetic information can prove that they were right all along. The geneticists were allowed to use the last remaining tissue from the skeletons molars, they also looked the teeth of a 6,075-year old skeleton, and that of a 2,500-year skeleton from a very close by island. Even though the DNA was severely damaged they were still able to sequence markers for about 6% of its genome, as well as two-thirds of the genomes of the other skeletons that were looked at. The markers were then compared to that of 156 indigenous groups worldwide, and found that the younger skeletons of 6,075 and 2,500 year olds were closely related to several tribes living in the Pacific Northwest. However, Shuka Kaa seemed more closely related to tribes living in South and Central America. This could simply show that all the tribes share DNA form the same ancient ancestor in Asia before anyone came to the Americas.  Shaku Kaa’s mtDNA and Nuclear DNA both suggest that he is very closely related to the other two younger skeletons looked at in this study.

As discussed in class as well as in an article by the New York Times, mtDNA or mitochondrial DNA contains only 37 of the 20,000 to 25,000 protein-coding genes in our body. It of course only comes from the mother, unlike the nuclear DNA that was collected which comes from both parents. Overall this research is important because it is important to know where we came from and the truths of our lineage. Ones true family history is often times unknown and changes as generations pass and people migrate.

http://www.sciencemag.org/news/2017/04/ancient-skeletons-show-direct-link-modern-tribes-pacific-northwest

https://www.nytimes.com/2016/06/24/science/mitochondrial-dna-mothers.html