The Gene for Hands Also Codes for What?

 In this NYT article, "How Did Hands Evolve? The Answer Is Behind You.", scientists had discovered a strange connection between the stretch of DNA called 5DOM that had been found in both mammals and zebrafish. It was found by Dr. Duboule and his colleagues, who were looking at molecular locks that sat along 5DOM. They had snipped 5DOM out of the DNA of a mouse embryo, and it ended up developing legs, but not feet. This led to more questions about when this section of DNA came about in animals, so Christopher Bolt, a graduate student at the time, looked through the zebrafish's genome and found 5DOM there too. This suggests that this set of genes was also present in the primordial ancestor of zebrafish and mammals.

 Dr. Hintermann took over the research and, using CRISPR, removed the 5DOM molecular locks from zebrafish embryos. The deletion didn't have much of an effect on the development of fins, but it did affect the development of the cloaca. When looking back at the same area in mouse embryos, the researchers discovered that the sequence codes for the urogenital sinus in mammals. Scientists are proposing that 5DOM went through evolutionary change, since it is easier to recode than to build a whole new sequence. Both structures that form are extremities that developed towards the far end of the body as well. There is more research needed on exactly why this change in 5DOM came about, but this is a starting point.

 Researchers are slowly finding more pieces of how the different gene codes for mammals came about with the shift onto land. This discovery at least gives a jumping point for how connected animals are and where mutations could have taken place in DNA, or how adapting to environments could have played a role in this.

Human Brain Genes Introduced to Macaques

Researches in China believed it would be a good idea to give monkeys human brain genes. Human copies of the MCPH1 gene were introduced into 11 macaque embryos. This gene is known to have an important role in the development of the brain in humans. This gene was introduced to embryos with a virus that carried the gene. Out of the 11 monkeys, only five survived. These five monkeys were tested, including MRI brain scans as well as memory tests. A controlled group was part of the experiment so they could make comparisons. The results showed that the tested macaques did not have bigger brains compared to the control group. One of the differences was that the tested macaques showed better results in short term memory tasks. Also, just like human brains, their brain developed over a long period of time. The main objective of this experiment, according to the researchers was to question the genetic basis of human brain. How the human brain have its own unique intelligence, which other primates do not have. The experiment was extended by using other genes such as SRGAP2C which is related to intelligence and FOXP2 related to speech and language.

This picture shows five cloned macaques 

If the monkeys being experimented end up being more smart like humans, then where are these monkeys going to end up? most likely locked up. The will not have a normal life or might not even like the same things that regular monkeys like including food. Overall, this is probably only causing harm to the macaques. Of course it would be interesting to learn and research on how evolution happened but what is the cost? very unfair to all the innocent animals.

IQ and Disease Testing in IVF Embryos'

A new genetic test is on its way to the Unite States that screen IVF embryo's for a low IQ and high risk diseases such as breast cancer, heart disease, and diabetes. People in society have always had the want to create the "perfect baby". New methods that have arose may make this possible. IVF embryonic genes are able to be tested for high risk diseases and low IQ created by the firm Genetic Prediction. These test have not been used yet but the firm is working closely with many IVF clinics so it can be made available to their customers. The firm reports that when it comes to intelligence can only determine "mental disability" in the embryonic state. These forms of testing is not available in the United States just yet.

The Genetic Prediction firm has become the first company to make polygenic risk scores in embryo's available. Their purpose of these tests is to screen out any of the embryo's testing for the risk of specific medical conditions. The test that they have created for "mental disability" is considered controversial where they do not have enough accuracy to determine the IQ for each embryo. On the other hand, they can determine certain outliers that give people the change to not pick the embryos that have a potential IQ below 25. It cannot be understood how many other genes are involved in low risk of heart disease and high intelligence. Any kind of genetic testing has been impossible to detect certain genes that play a role in diseases and development. Now with may of the technological advances, we are able to evolve testing strategies to ensure a healthy individual. I wonder if people in the Unite States would be interested in this kind of testing of IVF embryos. If these genetics test are available in the United States, I believe it would not get a warm welcome from everyone. I see it as picking and choosing a certain child, whereas we're all the same and each deserve an equal amount of love and attention.


Article: https://www.newscientist.com/article/mg24032041-900-exclusive-a-new-test-can-predict-ivf-embryos-risk-of-having-a-low-iq/
Related Article: http://americanpregnancy.org/infertility/in-vitro-fertilization/

Genetically Modifying Human Embryos

U.K. scientists are given permission to genetically modify human embryos. Scientists will now be able to alter the DNA of embryos, for research purposes only. This makes it illegal to use these genetically modified embryos and implant them in a woman. The entire purpose of this research is to better understand the earliest stages of embryo development.

The embryos that are being used are excess embryos donated by couples who have had "in vitro fertilization treatment." IVF is the process of combining egg and sperm in a laboratory dish and then transferring the embryo to the uterus. Scientists are concentrating on the first 7 days of the fertilized egg, in which one cell becomes 250 cells. Although there are many benefits of this research, people are afraid it may lead to "designer babies." Ronald Green, a professor, thinks that people designing their babies is bound to happen within the next century. However, U.K. would not be the first country to do so. China altered a gene in embryos that causes blood disorders.

Being able to alter the DNA of an embryo for the better, such as China did, is a good thing. However, once people get to choose their child's eye color and intelligence is where it becomes a concern. I believe children should be born they way they are meant to, and they should not be genetically modified unless for major health concerns. Hopefully, this U.K. experiment doesn't come to that. But like Ronald Green, I have a feeling it might in the near future.

First IVF Puppies

Scientists from Cornell University were able to successfully deliver a litter of puppies that were conceived through the process of in vitro fertilization. Scientists have been trying to accomplish successful in vitro fertilization in dogs since the 1970’s, but kept falling short. Scientist at Cornell University stated that the main challenges were “figuring out the optimal stage for fertilization of the female dog’s eggs and simulating the conditions in the lab for preparing sperm”. Eventually the team of scientists were able to transfer 19 embryos into a host female dog which gave birth to seven puppies. Five of the dogs were conceived from beagles and two were a mix of beagle and cocker spaniel. The embryos were cultivated in a dish in a laboratory before being implanted in the dog. The reason why this discovery is such a breakthrough is because scientists believe that the success of this experiment may help the future conservation of endangered species and may also help with gene-editing technologies that cure inherited diseases in dogs. Humans and dogs share more than 350 traits, and this breakthrough could help further the research of many genetic diseases.

I think that the success of this experiment is truly remarkable and that this will definitely be helpful when studying other genetic diseases in humans. I was surprised to learn that dogs and humans share over 350 traits. Hopefully in the future in vitro fertilization will be useful in the conservation of various endangered species.

Original Article

Human DNA Placed Into Mouse Embryos

Evolution of the human brain has always been a topic of interest for scientists over the years. Many have wondered how human brains have become so complex and why chimpanzee brains have lagged behind even though chimpanzees have almost all of the same genes that humans have. Scientists at Duke University have tackled this question and obtained some interesting results. More specifically, these scientists have found differences between chimpanzee and human genetic codes and observed how these differences affected embryonic brain development in mice.

For the study scientists focused on shorts pieces of DNA called enhancers that are a part of every genome. These enhancers regulate gene activity and are sometimes human specific. Until now none of these human specific enhancers had been shown to influence brain development directly.  The scientists searched through chimpanzee and human genomes to find enhancers that are expressed in brain tissue and early in development. Enhancers that were largely different between the two species were of high importance. In the beginning, 106 enhancers were narrowed down as being potentially important for discovering the differences in chimp and human brains. Out of these 106, 6 were thought to be involved in brain development. The enhancers were named HARE1-6, standing for human accelerated regulatory enhancers.  HARE5 showed the most promise as it is located near a gene, Frizzled8, which is known for its role in brain development and disease. The researchers directed their attention onto this enhancer and postulated that it enhanced Frizzled8 since HARE5 and Frizzled8 make contact in the brain.  

The HARE5 in humans and chimpanzees only differ by only 16 base pairs. However, the human enhancer was active earlier and more active in general in the mouse embryos than the chimpanzee enhancer. The activity differences between the two enhancers were detected at a critical time in brain development. The mouse embryos with the human HARE5 ultimately ended up with more neurons than those with the chimpanzee HARE5. As the mouse embryos developed more and more and came closer to the end of gestation the difference in size of the brains became noticeable. The mice that had human HARE5 had brains that were 12% larger in area than those that had the chimpanzee HARE5. The part of the brain that was affected was the neocortex. This part of the brain is involved in language and reasoning. 

This feat was astonishing, just narrowing down the enhancers in itself was a difficult and cumbersome task. Many other scientists have tried to do what the Duke University researchers did and failed. As a result of this successful study, a genetic reason as to why humans have bigger brains than chimpanzees has been discovered.

I feel that this is so interesting and awesome that it has finally been discovered. Humans are so closely related to primates, yet so different. It is interesting to realize that all of the differences are most likely due to some small change in the genetic code. I mean if just one different enhancer could make mice brains larger then imagine what a few differences could amount to. It is astonishing to think about the complexity of genes and how they work together to produce many different characteristics. 

Link to Article: http://www.sciencedaily.com/releases/2015/02/150219133104.htm

Additional Link: http://www.latimes.com/science/sciencenow/la-sci-sn-dna-chimp-human-brains-20150218-story.html 

                                                           Genetic Testing: Is it Ethical?

 In this article we explore the case of Amanda Baxley, who made the decision to have her children through the process of invitro fertilization. She had discovered that she had the gene for Gertsmann-Straussler-Scheinker disease otherwise known as GSS, a fatal disease. This disease has been passed down for generations and Baxley decided that she would not let her predecessors suffer the same fate. Over the course of ten years, the process of invitro fertilization has improved drastically. However, testing and the actual process ensures that a child at risk for a disability would be born healthy, the cost is often not covered under insurance.

There has been great debate on whether or not the procedure is ethical. Many question whether it is right to discard the embryo with a faulty gene. In regards to the ethicality of genetic testing an in vitro fertilization, I feel that if there is a possibility for a child with a high risk of disability to be born healthy and lead a normal life, the opportunity should be taken by all means. As an embryo. the sperm and egg have not developed into a living breathing human being and therefore discarded embryo's with faulty genes should not be seen is the loss of a life but the prevention of leading a difficult life.  

Primary Article: http://www.nytimes.com/2014/02/04/health/ethics-questions-arise-as-genetic-testing-of-embryos-increases.html

Secondary Article: http://americanpregnancy.org/infertility/in-vitro-fertilization/