Punnett's Square

An article found on Medical News Today along with another article talks about how the Zebra Fish can be used to understand how genes work in health and disease. The zebra fish shares 70% of its protein coding genes with humans, and 84% of its overall genome. Due to this astonishing fact, the zebra fish’s genome is one of three that has been sequenced in great depth. The other two are the human and the mouse. This genome will be crucial to studying diseases in humans in ways that cannot be studied. Zebra fish research has already been used to understand cancer, heart disease and muscular dystrophy. Scientists are hoping to use the genome to undertand the function of specific genes and develop medicines.

The zebra fish is unlike most other vertebrates. They have the highest repeat content in their genome sequences as well as genes that code for sex determination. The zebrafish also has very few pseudogenes,  or genes that have lost function through evolution, compared to the human genome.

“Armed with the zebrafish genome, we can now better understand how changes to our genomes result in disease,” said Professor Christiane Nüsslein-Volhard, author and Nobel laureate from the Max Planck Institute for Developmental Biology.

The brain communicates through different series of elaborate electrical pulses. Different behaviors require a different electrical pathway that are unique to that behavior, and they are very specific. However, if a group of neurons gets out of control, it can throw the brain’s whole electrical system out of control and cause epileptic seizures. Researchers at University College London, have developed a treatment for this by using what they’re calling “calming genes”.

By injecting a virus into brain cells, which goes through reverse transcriptase and codes to add specific DNA segments, the brain cells’ natural levels of inhibition, & calms them down, so that they don’t become over active. One of the researchers, Dr Robert Wyke, told the BBC: “It’s the first time a gene therapy has been used to completely stop these seizures.” Much more testing is needed before these drugs can be tested on humans, but the first candidates would be those who need brain surgery. This is becuase if the drug didn’t work or had adverse effects, that region of the brain could be removed.

Being that epilepsy hasn’t had any new drugs come along to help it in almost 30 years, this seems very promising. This “drug” is a form of gene therapy that will dramatically cut down on the side effects that current medications have. This may also be a broader approach to help more of the epileptic population, because only about 30% respond to current treatments.

In an article found on Science Daily, a recent study brings rise to a interesting topic that links genetics and spanking in boys to childhood violence.  The study stated that there is genetic factors that affect which kids will display aggressive behavior more than others.  This was determined by a group of researchers whom examined data of children ranging from 9 months old to 5 years in age.    The researches stated that they found a connection between genetic predisposition and spanking in boys but not in females.  The types of behavior that were displayed due to spanking and having a high genetic risk were disruptive behavior and temper tantrums.  They concluded that a reduce in spanking could help lower the amount of children that pose a chance at obtaining childhood agression.

An international group of scientists, including University of Utah biologist Richard M. Clark and researchers at a research institute called Ghent VIB in Belgium, has decoded the genome of the two-spotted spider mite (Tetranychus urticae). Interestingly, this is also the first genome of any arachnid that has been sequenced. It was revealed that this arthropod has 18,414 genes, 15,397 of which are expressed by being used to make proteins. In comparison with other arthropods, the spider mite uses a different molting hormone to shed its exoskeleton while it is growing, has only eight Hox genes (while most other arthropods are known to have 10), has only two main body segments instead of three because of its lack of Hox genes, and makes silk that is similar to spider silk except that it is 185-435 times stronger and spun from its head region rather than from its abdomen. Clark also mentioned that this silk may be useful for making biodegradable bandages and sutures because it is easy to obtain.

The two-spotted spider mite, shown here, is less than one millimeter long.

Having knowledge of the genome of two-spotted spider mites is important because they are related to house dust mites and other parasitic ticks that can transmit serious diseases to both humans and animals. They are also an invasive species and are a threat to global food production due to their need to suck plants such as tomatoes, peppers, cucumbers, strawberries, corn, soybeans, apples, grapes and citrus fruits dry, which often results in reduced harvests for farmers since they are able to consume over 1,100 different plant species, including the ones already mentioned. Alarmingly, scientists predict that due to global warming, spider mite plagues will increase because they reproduce faster at higher temperatures. The annual cost for pesticides used against these mites is about 0.5 to 1 billion dollars, and they are known to show resistance to different kinds of pesticides – the sequenced genome actually contains genes for detoxifying pesticides. The continuing study of their genome will be important in understanding how they are able to adapt to consuming new types of plants as well as resist pesticides, which will hopefully be the first step in reducing their numbers and understanding arthropods in general with more depth, which are fascinating enough simply due to the fact that they account for more than 83% of all described animal species.

The original research article is available here.

In this article, the new research was aimed to identify the genetic factors that lead to breast cancer, however, the research have found a link between the fat mass and obesity-associated gene (FTO). Study in Northwestern Memorial Hospital, illustrate that people with FTO have up to 30 percent higher chance of developing breast cancer. There is not a clear sign why the link exists. However, experts say that with this discovery it will lead them to form a personalized medicine, which could reduce the risk and allow better monitoring, and prevent illness. Virginia Kaklamani, co-direct of the Cancer Genetics at Northwestern University, says that this is a remarkable discovery. Every individual have FTO gene, however only 18 percent carries FTO variant. Right now, there is no testing available for FTO variant, however in future we will have this testing available.
With availability of this testing, we will better identity people who are at risk. I found this article interesting because it talks about the new discovery. It is interesting to know because this new discovery will reduce the risk and will helps us form a personalized medicine.

http://healthland.time.com/2011/10/27/british-scientists-grow-super-broccoli/#more-45784 (article link)

         In this article the sonic hedgehog gene or SHH  is found on chromosome 7 and codes for a signalling protein crucial for determining the placement of limbs and organs in the developing embryo. When the embryo first forms various signalling proteins are established, there are high concentrations  where the protein is being secreted and gets lower and lower in concentration with increasing distance from the source. This interactions of the proteins make up a pattern, here is where the SHH gene comes in. If SHH does not work, then this is a huge problem.  “Hedgehog genes” is a term that scientist have come up with to describe what happen in fruit fly embryos that are genetically modified to lack SHH and similar genes were covered in spine-like projections.  The consequences of mutation in the SHH gene in humans is very important, because if the embryo does not survive its due to its body layout is completely out of order, however, if the embryo does  indeed survive, they have big problems with facial and brain development.

When I did not think the subject of pathogens could amaze me anymore then it has, up pops an intriguing article. During the 1300’s over 50 million Europeans died because of the bacteria Yersinia pestis. For those who do not know what that is, Yesinia pestis is simply the bacteria that the Black Death. Recently an international team of scientists decided to put their mind together, dig up the skeletal remains and find this particular pathogen. By extracting, purifying and specifically enriching the pathogens DNA, researchers were able to sequence the entire genome of the Black Death. By doing this scientists will determine how Y pestis has evolved through the centuries and see what makes it so deadly.

http://docp.edublogs.org/yersinia-pestis/ Another great link!

http://www.sciencedaily.com/releases/2011/10/111012132653.htm?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+sciencedaily+%28ScienceDaily%3A+Latest+Science+News%29 Where I got my source from.

A recent article states that there maybe hope for those with celiac’s disease. David van Heel, a astrointestinal genetics professor at Barts and The London School of Medicine and Dentistry, meet up with a group of reasearchers from around the world. They have studied the genetic maps of over 9,400 celiacs. The research is hoping to expand on treatments and cure’s for those with celiacs. Although on 3% of people that have celiac’s are diagnosed. The study is hoping to help diagnose the undiagnosed. The research claims to have made a substantial amount of progress over the genetic map studies. This study will eventually help increase awareness and treatment options.

Celiac's Disease.

Before I read this article I would of bet good money that identical twins genes are identical, and I would have lost. Research done by Geneticist Carl Bruder of the University of Alabama at Birmingham and his colleagues showed the differences in the genome of two identical twins. Until Bruder came upon these findings any differences in the lives of twins was labeled as an environmental cause. Now the census is to look at  the twins and their genome. Maybe it is not all environmental causes that allow one twin to have a disease and the other to be healthy. The article told about how twins have multiple copies of genes. These areas, instead of having a two sets of genetic data, have multiple gene copies. These areas are in a state of copy number variants. The easiest way for researchers to separate nature vs nurture was to do testing on twins. Because of the previous notion that there were genetically similar it eliminated a variable, but that variable may be back after Carl Bruders findings. But instead twins can help scientists find specific gene locus that identify genetic disorders. Another interesting point of this research was to help put the right twin in jail! In Virgina alone there are 80 pairs of identical twins in jail. If one twin is seeing committing a crime, and the other has no alibi it can be hard for a court to decide who is guilty. “So hopefully looking at copy number variants of two twins can help sort that out.”