Madison+M.

=Evolution of the German Shepherd due to Selective Breeding=

This photo shows the changes the German Shepherd has gone through since the early 1900's.
====Many breeds of dog have evolved due to something called “selective breeding.” According to the biology online dictionary the definition of selective breeding is: “The intentional breeding of organisms with desirable trait in an attempt to produce offspring with similar desirable characteristics or with improved traits.” Unfortunately, many of these desirable traits being selected for are for appearance only. This is important for people who enter dogs into shows, as they look for specific traits. However, the dogs are becoming sick due to the changes we desire. Some dogs evolved to have smaller snouts causing breathing problems, while others hips are so low they cannot move properly. One dog which has changed a lot over the years is the German Shepherd.==== ====The breed was first standardized by Captain Max von Stephanitz in the year 1889. It was bred for its personality traits and appearance was not important. Stephanitz used the phrase “utility and intelligence” when referring to the German Shepherd. The dog was originally bred to help in the war as a messenger, tracker, supply carrier, etc. In 1915 the first dog show was held. By this point the dog’s physical traits had begun to change. Stephanitz also noticed that the dog’s temperament was not as stable as it had once been. If we fast forward to the 1950’s we can see that by this point the dogs pigment is beginning to fade, they had straighter front legs, and weaker ears.==== ====In modern day the Kennel Club has standards for every breed of dog. The Kennel Club is responsible for some of the biggest dog shows. They have descriptions of how each German Shepherd should look and this differs greatly from the original look of the dog. According to their website, the dog needs to be longer than it is tall, have more curves than angles, and they must give a feeling of masculinity or femininity, depending on their sex. How can breeders be sure they will get pups to meet these standards? They use selective breeding, which can have hazardous health effects on the dog. Basically, when selective breeding you can manipulate the animals you are breeding so the offspring will produce the desired====

====phenoty pe. Say you have one German Shepherd that has a straight back and one that has the curve to its back. You wouldn’t want to use the first dog for breeding because it has an undesired trait. Instead you would ideally want to breed two German Shepherds with the curved backs. You can also use selective breeding to get a certain temperament in the offspring. ==== ====However, when you continually breed a dog to have certain characteristics it can destroy its health. The most common medical issue with the breed is hip dysplasia. Hip dysplasia occurs when a bone cannot fit into the socket. Since the bone cannot fit properly, it grinds against the socket causing pain in the animal. This medical issue can occur within the first four months of a German Shepherd’s life. Another medical issue this breed is prone to is panosteitis. This health problem effects the forelegs and causes them to be inflamed. The pain can cause the dog to be unable to walk properly, and it also occurs during the early stages of their lives. ====

==== As you can see the German Shepherd has changed since its beginnings. The motto once given to the breed, “utility and intelligence,” is being taken over by physical appearance. Breeders desperately try to produce offspring that resemble the American Kennel Clubs description. Hopefully in the future people will recognize that these changes we are selecting for are causing huge health risks in the pups. ====

This image shows the body type of a modern day German Shepherd.
=Video:=

media type="youtube" key="pYadOOzENhE" width="560" height="315"
=Additional Sites for More Info:=

[] This website talks about hip dysplasia, plus the cure and prevention. [] This site talks about panosteitis the cause and diagnosis.

https://dogbehaviorscience.wordpress.com/2012/09/29/100-years-of-breed-improvement/ This site shows the evolution due to selective breeding in many breeds using pictures.

[] This site shows more examples and pictures of how the German Shepherd has changed.

=Sources: =

1. [] 2. [] 3. [] 4. []

= = =Heart Disease and Genetics=

November 20th, 2015
What is heart disease? Heart disease can fall into a few categories like: blood vessel disease, coronary artery disease, irregular heart beat rhythm, etc.

Heart disease is said to be a hereditary disease, but what does that actually mean? Genes and certain traits can be passed from one generation to the next. It is all dependent on what genes your mother and father had. A single change to one gene can affect your risk of heart disease. Some traits (alleles) are dominant, meaning that a dominant allele can “mask” a recessive allele. The dominant allele in this situation would be a person who doesn’t carry traits for heart disease. The recessive allele would be a person who is a carrier of the allele for heart disease. Heart disease is generally passed down in an autosomal dominant pattern. This term means that if you have an autosomal dominant trait, you have one dominant allele and one recessive allele. You then have the possibility to pass these traits unto your children. It is all dependent on what your partner’s alleles for heart disease are.

 If your mother has the allele for heart disease (recessive), but your father only a carrier (autosomal dominant) then you would have a 50% chance of inheriting the allele for heart disease. We can represent these traits with letters and then see the results of their children’s genes through a punnett square. If a person who doesn’t carry heart disease has the dominant allele is can be represented by “H.” If heart disease is the recessive allele it can be represented by “h.” The cross represented below would be HHxHh:

|| hh ||
 * Hh
 * Hh || hh ||

 Here is an example of a punnett sqaure with Mendel's pea plant breeding experiment. Punnett squares can be used for all types of genetic problems and you can make punnett sqaures for 2 different characteristics as well.

You can also create a pedigree chart for your family, which can help you determine what genes your children may have. A pedigree chart is sort of like a family tree, but it is used to discover traits passed down. This is helpful to get a big picture view of your relatives genetics as well as your own.

As you can see, the males are squares and females are circles. In some pedigree charts a shape may be shaded to show the recessive gene.

Genetic testing is also something becoming more popular. To do a genetic test, a sample of your DNA is taken and then studied for pathogenic mutations (disease causing mutations). The whole family tree gets studied as well, because knowing the genes of relatives is crucial. Getting this sort of testing done can tell someone suspected of having these traits if they carry them or not. It can also help families get their loved ones help and allow them time to prepare for future illness. However, there is no way to change the genes passed down at the moment. There is however, talk of this being done in the near future with "designer babies." Researchers say that they would be able to prevent many diseases by changing certain genes. This image shows the pathogenic mutation found during genetic testing vs. a normal allele.

= Video: = = = ====This video details how dominant and recessive genes work, shows a couple pedigree charts, and also talks about how it relates to a few other medical conditions. Although heart disease is not specifically mentioned, you can see that the genes would work the same way in passing on the condition.==== =media type="youtube" key="C_tHNMZF_Q0" width="560" height="315"= = =

=Additional sites for more info:= This site sums up how heart disease is passed on and also gives examples of types of heart diseases that can be inherited as well as more info on them - https://www.bhf.org.uk/heart-health/conditions/inherited-heart-conditions

This PDF powerpoint details how you can create a pedigree chart. It also talks about XX, XY chromosomes - http://www.bogari.net/Bogari/Medical_Genetics_files/3-1%20Patterens%20of%20Inheritance.pdf

This site shows you how a punnett square works and also how to solve the punnett sqaure to see the traits of offspring - http://www.hobart.k12.in.us/jkousen/Biology/psquare.htm

You can find out a little more about how genetic testing works here - http://www.health.harvard.edu/heart-health/update-on-genetic-testing-for-heart-disease

This site talks about designer babies - http://www.bionetonline.org/english/content/db_cont1.htm

=Sources:=

1.[]

2. hopkinsmedicine.org/heart_vascular_institute/clinical_services/specialty_areas/center_inherited_heart_diseases.html

3. []

4. [] = = = = =Genetic Engineering in Animals=

October 22nd, 2015
This image shows a brief explanation of how a transgenic animal is created with DNA.

====Genetic engineering is the process of taking DNA from one organism and adding it into another organism to create a new trait in the second organism. As an example, farmers genetically engineer their crops to withstand more environments, grow bigger, or last longer. However, genetic engineering can also be done on animals. One example is adding DNA to fish so they will grow bigger and faster. However, this process can be done to other animals as well. In the beginning this engineering was used to make bigger cows, or to improve quality of milk. You can actually genetically engineer a cow to produce milk with human proteins in it.==== This image shows how we can achieve bigger chickens in much less time due to genetic engineering.

Now it is used for many different reasons, one of which is medicine. The medical field is now interested in creating animals for testing with a higher risk of cancer and other diseases. They say this will increase how accurate their tests are. Researcher’s say that this will impact the medical field greatly. One of the biggest studies happening with this now is how we can use animal tissues for human transplants. This type of research is known as xenotransplantation. Pigs are the animal of choice when it comes to using animals for human transplants, but there is a problem with using regular pigs. Tissue from regular pigs is rejected within minutes, but the transgenic pig tissue can last up to six months. Transgenic pigs are also looking to be a prime animal to help with diabetes. Pancreatic islet cells for a “human CD46 complement inhibitor gene” show amazing results. It showed diabetes being cured for three to six months. This will likely be one the first tissues tested in humans. Although there is a pros to genetic engineering, is it ethical?

Many questions are raised around this topic. Is it ok to mess with an animals genetics? We tend to make decisions for the creatures who cannot decide for themselves. We are constantly pushing the limits and then asking how far is too far? One example is a study done by Ning Li. His plan was to genetically engineer a cow to produce human breast milk. It worked successfully, but over the course of two experiments in the study, only 26 of 42 calves survived. Are studies like these ethical if it is only producing something we already have? In my opinion, no. What about a study to make cats glow in the dark? In South Korea, scientists used skin cells from Angora cats and injected into them a virus that would give instructions to make a red fluorescent protein. Finally, Glofish were created. Scientists took protein from a jellyfish and inserted it into the Zebrafish. This created the trait of being able to glow in the dark. These fish are now for sale in parts of the US, but California, Europe, and Canada have banned the sale of Glofish. These are just a few of the studies that have caused a lot of controversy when it comes to genetic engineering.

These are the Glofish that are for sale currently.

=Video:media type="youtube" key="JVIznPgdQSM" width="332" height="205" align="right"= This video goes along well with what I discussed above. It lists examples of studies done on animals. I have already mentioned some, but it has many other examples such as "robo mice." it also brings up ethics ad asks the viewer questions about how far we should go with genetic engineering in animals.

=Additional sites for more info:=

Overall concept and explains why DNA and protein are important in genetic engineering: []

Lists pros and cons of genetic engineering and also discusses ethics: []

The FDA (Food and Drug Administration) compiled a list of different articles of what they allow: []

This is a list of some of the weirder animals that have undergone genetic engineering. Each paragraph also contains links to other sites that have more info about each study: []

=Sources:=

1.[] 2. []

3. []

4. [] 5. []