Saturday, September 24, 2022

Humans Evolved with the Bacteria in their Stomachs

Scientists have discovered that species of bacteria in human stomachs may have had some influence on human evolution. Most bacteria in human stomachs are similar, but there are some species that show the differences in some human populations.  Scientists have tested for codiversification by collecting samples from people around the world and comparing them. As early humans spread out across the world, there were different sources of food that humans had to acclimate themselves to. Phylogenies were created to understand how people of different regions and the microbes in their stomachs are related. The scientists were able to trace people with relatives in Europe, Asia, and Africa.

Codiversification occurs in organisms that live in symbiotic relationships. A symbiotic  relationship occurs between very different organisms. There are three main examples of symbiotic relationships, which are mutualism, commensalism, and parasitic relationships. Mutualistic relationships are when both organisms benefit, commensalistic relationships are when one organism benefits and the other is not affected, and parasitic relationships are when one organism benefits and the other is negatively affected. Humans and the species of bacteria in our stomachs is a mutualistic relationship because humans are able to digest their food and the bacteria have a habitat and a food source. 

I think that it is good that scientists are finding other ways to trace the origins of humankind. It is difficult and expensive to dig to find skeletons and other things that give answers to questions about the origin of humans. Other scientists have commented on this new information and they have made the point that the relationship between humans and their bacteria could create microbiome treatments specific to a population of people based on their ancestry. Personalized medications could help patients that experience issues with their stomachs, since every patient is different and could react differently to generic medicines. The reason that stomach medications might not always work is most likely because of the diversity of the species of bacteria in every person’s stomach. 

Friday, September 23, 2022

Herpes Virus has been found to be around for several of years

 An article was found that researchers have pinpointed the first happenings of the Herpes Virus after several years. Researchers could record the early sights of the herpes virus through sequenced ancient herpes virus genomes for the first time. Although The Herpes virus today is a virus that causes lip sores, back in the day, most herpes cases were passed from an infected mother to her newborn baby rather than through kissing, which it is known for today. Dr. Charlotte Houldcroft, from the department of genetics at the University of Cambridge, in England, explains that genetic data for herpes only went back to 1925. Dr. Houldcrroft and Dr. Meriam Guellil, from the University of Tatu’s Institute of Genomics in Estonia, screened ancient DNA sampled from about 3,000 archaeological findings and only got four herpes hits. DNA was extracted from the roots of the teeth of infected individuals. The herpes virus often flares during mouth infection, and the ancient corpses included two individuals with gum disease and one who smoked tobacco. For the four hits of evidence, the individuals lived at various times over thousand years. One male lived during the Iron Age about 1,500 years ago. Another two sampled individuals were found near Cambridge, one female from an early Anglo-Saxon cemetery dating from the 6th to the 7th centuries. The last was a young adult male from the 14th century who was buried on the grounds of a medieval Cambridge hospital and had suffered what the researcher called “appalling” dental abscesses. The fourth sample was from a young adult male from Holland who they assumed was a clay pipe smoker. With the researchers comparing the DNA of these ancient cadavers with the herpes samples from the 20th century, they were able to analyze the differences and estimate s mutation rate and even a timeline for the evolution of the virus. About 5,000 years ago, the virus overtook all other viruses and increased the transmission rate, which was believed to be from kissing. On average now, two-thirds of the global population that is under the age of 50 carry the Herpes Virus (HSV-1).

Wednesday, September 21, 2022

Can't comb your kids hair? This gene may be to blame

A geneticist in germany has linked three genes to a rare condition referred to as "uncombable hair syndrome". Although very rare, with only about 100 cases reported, 71% of cases were attributed to a mutation in the PADI3 gene. This gene is responsible for the formation of the hair shaft, and this mutation causes the hair shaft to be formed with a groove in it. This causes the hair to stand up and stick out, no matter how much it is combed. A small percentage of cases were attributed to mutations with the TGM3 or TCHH gene, but a quarter of the cases are still unexplained. 

The condition seems to improve with age, and has no side effects detrimental to the health of the individual. 

Relevant article: 

Monday, September 19, 2022

A mutation that may have given Homo sapiens a neurological advantage over Neanderthals

 A group of molecular biologists and geneticists in Germany had an interesting breakthrough when studying differences between the brains of Homo sapiens and Neanderthals.  Although scientists have known for a while how the brain sizes of these two hominin species compared, there was not much evidence about the structure or neurology of the brain. Now, however, these German scientist have identified a key genetic mutation between the two. Modern humans have a mutated version of the TKTL1 gene found in Neanderthals and it appears to allow for a more efficient creation of neurons in the brain. A great number of neurons could have contributed to an increase in neuroactivity/intelligence and therefore Homo sapiens' evolutionary success as opposed to Neanderthal's extinction. That would be incredibly significant for a mutation that is only different by one amino acid.

Other scientists are a little more hesitant to accept this proposal. The article discusses how this researched focused on only one cell line and that they largely ignored data that was not Western European. These critics are not turning down the proposal altogether. They are simply calling for wider and more extensive studies that could contribute to this finding.

Personally I think the concept of this research is very fascinating. One of those big life questions that I have is why out of all the early hominin species, we were the only ones to make it this far. This article exposed me to a potential contributing factor and gave me hope that more could come soon. Overall, I think the article was well written. I do wish, however, they had talked more about how the German scientists accessed the Neanderthal DNA to compared it to modern humans.

Gene in Brain Linked to High Human Intelligence

A team of European scientists conducted studies on a gene within the human brain, known to be connected with the high intelligence of humans when compared to other species. The scientists inserted the gene, ARHGAP11B, into organoids of chimpanzees which are the closest living relatives to humans. An organoid is a lab-grown group of cells or tissues that have some of the functions of an organ. Organoids were used for the study since scientific experiments involving altering genes have been banned in Europe out of ethical concerns. The chimpanzee organoids introduced to the ARHGAP11B gene showed an increase in neurons and brain stem cells related to brain growth. The scientists in the study found that the gene could enlarge a primate's brain but say further study is needed to determine the size of a role in human brain evolution. Likewise, they also found that when the gene was removed or inhibited in human organoids, the functioning of the cells decreased to the level of a chimpanzee. 

This study showed just how important the ARHGAP11B gene is to the development of the human brain. I think that this study gave great incites into how the human brain evolved and the genes responsible for its high-functioning. I am glad that we have the technology like organoids to develop experiments that we can use to study genes like this, and I how that more studies on this gene are done in the future. I'm sure there is a lot to learn from this gene and even medical applications it has concerning brain development, functionality, and disorders. 

Sunday, September 18, 2022

Genetic Heart Conditions Could be Cured with New Gene Editing Technology

Doctors from the US, UK, and Singapore have collaborated to cure genetic heart conditions by “rewriting” DNA. Base and prime gene editing will be used in the heart to silence incorrect genes. This will help direct the heart muscle to work properly. Heart muscle abnormality genes have a high chance of being passed on through generations. This new technology will reduce the number of deaths, heart failures, and heart transplants by fixing gene mutations. Errors in genes will create errors in DNA translation . DNA is turned to mRNA by adding matching nucleotides in the process of transcription. The mRNA then goes to the ribosome of the cell, where the mRNA is translated into proteins. If the wrong proteins are created due to DNA mutations, then the heart will not be able to function properly, since the muscle of the heart relies on certain proteins to contract and relax. Blood will not be able to reach all of the body if the muscles of the heart are too weak to pump. 

I think it’s important that base and prime gene editing is perfected, because there are many people that need heart transplants, and it is very difficult to find matching donors. There are also many other ways that this technology can be used. If it’s successful in the heart, then it could be applied in other areas of the body, which would reduce the number of people in need of an organ donation. Cancer is caused by DNA mutations, so this could also be applied to fix the errors in DNA that cause the cancer cells to rapidly divide and spread. 

Thursday, September 15, 2022

Researchers found a species of Jellyfish that are effectively immortal

In an article written by author Veronique Greenwood, she talks about how a small species of jellyfish known as Turritopsis dohrnii, that although these jellyfish swim and eat like many other jellyfish, they have a secret that sets them apart from other sea creatures. Turritopsis dohrnii live in the Mediterranean Sea and are secretly known to turn their old age back into their young selves. For Turritopsis dohrnii, when their bodies get damaged, the mature medusas can turn back time and transform themselves to their immature life stages. To do this, T. dohrnill sheds its limbs, allowing them to drift around in the water column and morph into a polyp form, which then allows them to attach themselves to rocks, plants or other sea life. After researching the jellyfish’s genome to search for the gene that controls this unusual life cycle, the only scientist, Shin Kubota at Kyoto University in Japan, found, after sequencing the genome, is that the jellyfish had extra copies of a particular gene. These additional genes allowed the researchers to see that these genes protect and repair the jellyfish’s DNA, which is an essential aspect of their survival. To test this rejuvenation process, the researchers put Turritopsis dohrnii under stressful conditions by not feeding them. The adult medusas shrank into smaller sizes, sprouted into polyps, and began remaking their adult bodies. During this process, the scientists captured snapshots of what genes the jellyfish were using in each stage of their development. In each phase, the scientists took jellyfish and froze them to turn them into mush to extract their mRNA, which gave them records of which genes were being used to make proteins. The scientists found that in the adults, their genes were relatively active, meaning they were used more frequently to make proteins. And as the jellyfish descended into the polyp phases, their genes became quieter, making less protein to form those smaller sizes.

Wednesday, September 14, 2022

Gene Study Spots Discovered that are Connected with Autism

 Autism is a spectrum of developmental disorders that impacts many aspects of life, such as communication, learning, behavior, and interactions. Every person is impacted differently, and the levels of severity vary from person to person. Scientists did not have a defined cause of the disorder, but they do believe that the condition is hereditary, and certain genetic conditions, such as Fragile X Syndrome or Down Syndrome can increase the chances of developing Autism. Autism is something that a person is born with, but symptoms do not typically show until a few years into a person’s life. Autism is not something that can be cured, but symptoms can be managed with therapy and other treatments. 

Researchers have now found that Autism is linked to 250 genes in the body. These genes impact mature neurons. These genes are also associated with schizophrenia. In other cases of slower development, genes tended to impact neurons in early stages of development. This proves that Autism is a genetic risk factor, caused by mutations in genes. This means that if scientists wanted to prevent or cure Autism, then the approach for the cure would be genetically targeted. In the past, families would attend genetic counseling to find out the risks for having autistic children, but could not do much if the chances of having an autistic child were high. 

Overall, I would love to see patients be cured from Autism, or have ways to prevent it. Life with Autism is very difficult because not everyone understands the complexity of the disorder, because of its large variety of effects. Autism is difficult to research since symptoms are so different in each patient. Any information that is discovered is crucial to finding a cure. Now that scientists know what genes are connected with Autism, the best way to approach the cure is to prevent it before it starts. However, I do think that treatments would be very expensive, and there would be a very small chance of insurance companies covering them. Insurance companies tend to only cover what is medically necessary, and Autism isn’t always a life threatening condition.