Name: Benjamin Leamey Student Number: 11577028 Course: ASC221 Phone no.: 0422176073 Email: ben.leamey@gmail.com Lecturer: Sam Pant Subject Code: ASC221 Subject Name: Animal Genetics Assignment No.: 1 Due: 18 September, 2015 Word count: 1000 No. of pages: 8 Karyotypes: Horseplay or nay? Introduction Karyotyping is a test that can be performed on a eukaryotic cell to examine the number and appearance of chromosomes in the nucleus. Karyotyping can be used to help identify genetic problems as the cause of a disorder or disease, such as Down syndrome. A karyotype test is very versatile, and can be performed on almost any tissue, such as blood, bone marrows, amniotic fluid, and if need be, the placenta of a pregnant woman. To make …show more content…
a karyotype, scientists take a picture of the chromosome from one cell, cut them out, and arrange them using size, banding pattern, and centromere position as guides. This allows for any structural changes in the chromosomes of an individual to be noticed, as well as providing the number of chromosomes present. This experiment involved the examining of karyotypes from either a normal human male, or a horse that had an undiagnosed genetic disorder and may have had chimeric lymphocytes containing X and Y chromosomes or X and X chromosomes.
Karyotyping is very suitable for this experiment, “…we are able to arrest the dividing cells in metaphase by the addition of colchine and an acetic/menthol mixture, causing the cells to burst and spread chromosomes.” (Urwin 2015). We are performing this experiment to determine if from the samples it is a normal human male or a horse suffering from lymphocytes, as many genetic diseases in animals and humans are a result of alterations in chromosomal structure, such as translocations, deletions and sometimes mutations …show more content…
themselves. Materials and Methods The procedure was followed mostly to standard as written in Urwin, (2015, p. 7-9), as well as all materials required were stated clearly throughout the method. Some alterations needed to be made to the method, these alterations were as follow: • In step 2 and step 4 of “Colchine Treatment and fixation of peripheral blood lymphocytes”, it is noted that instead of centrifuging the tube at 400g for 5 minutes, was corrected to stating it must be centrifuged at 2200 RPM for 5 minutes. • In step 4 of “Making and staining chromosome metaphase spreads”, a writing error had occurred, and a correction needed to be made. The correction made was to dip Slide 1 briefly into jar 2, 3 and then into 4 for 5 minutes, and not dip briefly into jar 2, 3 and then into 3 for 5 minutes. Results Sample A3 shows evidence of belonging to a human, seen in the physical count of chromosomes readily available for pairing. This sample also provides further evidence that the sample of blood has come from a female, seen in the presence of two X chromosomes. Sample B23 shows evidence that the blood has come from a horse, shown through the significant increase in karyotypes, and the structures are significantly different to that of human karyotypes. It is also believed to be a female horse, seen through the presence of two X chromosomes Discussion It is evident that karyotyping is an effective way in distinguishing chromosomes of not only humans, but also other species such as horses.
These two blood samples that we observed were the karyotypes of a female human and a female horse. What is significant about this experiment is the fact that neither sample A3 or B23 suffer from any form of variance. We can confirm that the human karyotype is healthy, supported by Pathology (2015), and the horse karyotypes are also healthy, with evidence from Horseman (2015). From the images provided we can see there is no significantly apparent mutation or missing chromosomes. As a karyotype test provides information about the number of chromosomes a person has, the structure of their chromosomes and the sex of the individual, it is able to distinguish if said person will suffer from any sort of disorder, such as Down syndrome. Down syndrome is a congenital condition caused by an extra chromosome. “For example, if a human karyotype depicts that a patient has three copies of the 21st chromosome, instead of two, the patient is diagnosed with Trisomy 21, also known as Down's syndrome”. (Innovateus.net, 2015) This is one significant way that karyotyping is used in the modern
day. The use of Trypsin and Giesma in banding seems to not have been present in either sample A or B, however that may be a result of a low quality camera being used to capture the images. Karyotype testing with the use of fluorescent dyes that bind to specific regions of chromosomes in others allows for a clearer image of chromosomes pairing to be made, as homologous pairs are the same colour, as well as patterns and crossovers becoming more easily recognisable. With the use of technology alongside this, “Slight variations in colour, undetectable by the human eye, are detected by a computer program that then reassigns an easy-to-distinguish colour to each pair of chromosomes.” (Biology.arizona.edu, 2015) karyotyping proves to remain extremely effective in the medical field. However, due to the intrusive nature of karyotyping, requiring a sampled tissue such as blood, cultured skin or bone marrow cells, a new test in 2013 emerged that seemed to make karyotyping obsolete for detecting the Down syndrome disorder in pregnant women, “…A new, non-invasive screening test for Down syndrome would allow some women with high-risk pregnancies to avoid amniocentesis…”. (Harvard Gazette, 2013) This advancement in technology can be administered earlier in a woman’s pregnancy than other screenings, potentially early enough to allow interventions aimed at improving a Down syndrome baby’s cognitive function. Samples A3 and B23 provided us with two, healthy females, one human and one horse respectively. The ability to determine if an animal suffers from a genetic disorder serves as a great resource and tool in the animal industry, useful for determining if an animal suffers from reproductive problems (infertility or subfertility), ambiguous external genitalia or poor development and growth. References • Urwin, N. (2015). Experiment 1 Karyotyping. ln ASC221/ASC421 Animal Genetics Laboratory Manual (p. 6-10). Wagga Wagga, NSW: School of Animal and Veterinary Sciences, Charles Sturt University • Biology.arizona.edu,. (2015). New Methods for Karyotyping. Retrieved 15 September 2015, from http://www.biology.arizona.edu/human_bio/current/new_karyotyping/new_karyotyping.html • Harvard Gazette,. (2013). New test for Down syndrome. Retrieved 15 September 2015, from http://news.harvard.edu/gazette/story/2013/10/new-test-for-down-syndrome/ • Innovateus.net,. (2015). What is a Karyotype?. Retrieved 16 September 2015, from http://www.innovateus.net/health/what-karyotype • Horseman, T. (2015). More Discussions of Horse and Man. Hglanham.tripod.com. Retrieved 18 September 2015, from http://hglanham.tripod.com/Horses/horses23.html • Pathology.washington.edu,. (2015). Cytogenetics Gallery. Retrieved 18 September 2015, from http://www.pathology.washington.edu/galleries/Cytogallery/main.php?file=human%20karyotypes
79%, were heterozygous. We concluded that it is possible to examine small amounts of DNA by
I can remember being a little kid and listening to stories my Grandpa and Great Grandpa told about the mustangs that used to be around the Black Canyon. They used to tell stories about when they would put their mares out with the mustangs during the winter to get bred. Then they would go out in the spring and catch their mares. They told stories of the times they had to chase the mustangs from the fields during the winter so the cattle could eat. They told of when they would go and capture the colts from the herd to keep for themselves. I can even remember the last one they ever had. He was at least 25 years old when I saw him. The last I knew of the mustangs Bureau of Land Management (BLM) rounded the herd up and that is all I ever heard.
My periodic table on horse breeds. I choose this because I love horses. I love riding them, caring for them, and just being around them in general. I organized the horse breeds into four groups - ponies, light horses (usually riding horses), and draft horses (usually working horses), and other horses (miniature horses, gaited horses, etc.).
The American horse racing industry has been admired by generations upon generations. Although it is a very cherished sport, like any other sport, there are many issues involved. The major issue that I find is that many owners make the decision to breed when there are other solutions. The Jockey Club, also known as the head council for the American Horse Racing Industry, should be addressing the major issue of overbreeding in the American horse racing industry.
Grand champion! I was riding Fancy, a paint horse, at the Dallas County Fair in the Horsemanship class. In this class, I had to complete a pattern and it was judged on how well each horse and rider completed the pattern. The judge felt that Fancy and I performed best and awarded me with a big purple ribbon and a trophy with a horse on top. At the end of the fair, all of the grand champions were announced before the races. That was the final reward for successfully showing a horse in competitions.
Both of these methods can help determine and eliminate genetic disorders, as certain conditions can be screened out using these technologies. As discussed in Meseguer et al., more than 300 diseases have been related to sexual chromosomes till date. Case studies also argue the important role of these methods in family balancing for varied family dynamics who aim to compensate their family with a representation of the other sex (Meseguer et al., 2002). Critics have also mentioned that with an increase in demand, these methods could become more economical and widely available, including to couples who may need it due to medical
For centuries people have enjoyed horses in various ways. From racing Thoroughbreds to western pleasure, the equine sport can be observed around the world. But, behind the glitz and glamour of horse shows, there is also a dark side. Nowadays, some horse people will use harmful shortcuts to get a leg up in competition. “ Pushed beyond their limits, most horses are subjected to cocktails of legal and illegal drugs intended to mask injuries and artificially enhance performance.” (PETA). Many trainers will use extreme, abusive techniques in the name of competition.
The fetus may measure under expected weight, and with later ultrasounds, physical abnormalities may be seen. The use of an ultrasound is not a full proof method of diagnosis for trisomy 18. During the end of the first trimester, pregnant mothers are given the option of prenatal screening to assess the fetal risk of certain chromosomal abnormalities, including trisomy 18. This testing referred to as combined test, combines results from the mother’s blood and the ultrasound results. If results suggest a higher risk probability, a later more conclusive test will be scheduled. During the 15th to 18th week of pregnancy, an amniocentesis or chorionic villus can be performed to have a detailed analysis of the fetal chromosomal material which will show any abnormalities in their karyotype. There is a slight risk with both procedures of injury of the fetus or possible miscarriage. Newer testing has been developed as “non-invasive prenatal diagnosis,” which involves extracting fetal DNA from the mother’s blood sample. After birth, diagnosis is suspected based on physical attributes of the infant. As with before birth, blood testing for chromosome analysis is used for confirmation testing.
The roots of animal experimentation began in the early 1600s when the world expressed in interests on the functions of animals and their uses in human life. However, it wasn’t until the incident regarding the drug thalidomide in 1960 did the government make it a requirement for drugs be tested on animals. During the incident, millions of women took the medication believing that it would be a source of relieve from morning sickness, not knowing however that it would cause irrevocable effects on their unborn children (Watson 4). Although the ruling seemed to provide a sigh of relief to some, the very idea of placing animals in strange uncomfortable environments and experiencing pain and euthanasia angered many. According to the American Anti-Vivisection Society, commonly known as AAVS, It is wrong to treat animals as objects for the purpose of scientific research, and to cause them pain and suffering (“Animal Research Is Unethical and Scientifically Unnecessary”). Although the arguments against animal experimentation seem credible, animal testing on medicines and products are necessary in order to insure the safety of human beings.
he horse, Equus ferus caballus, is a subspecies from the family Equidae. Over the past 50 million years, through survival adaptations, the common horse has evolved from a relatively small, multi-toed animal into the large, single toed animal known today (Wilson,. Mammal Species of the World (3rd ed.). Baltimore).
The procedure of genetic screening embryos allows the finding of a defective gene in an embryo. In many countries there is already a widespread programme to screen for the chromosome abnormality. Since this technology can change the information at the level of individual?
A Karyotype is when you cut out individual chromosomes from a picture and rearrange them. There are matching pairs of chromosomes these are called homologous pairs. Each pair is given a number. One of each pair came from the mother and one of each pair came from the father. The pairs can be distinguished as each pair has a distinctive banding pattern when stained. There are two sex chromosomes and the rest are called autosomes. In most karyotype the sex cells are kept to one side so that the sex can be seen easily. In females they have two X chromosomes and in the males they have an X and a Y chromosome. The Y chromosome has a portion missing and is therefore smaller then the X chromosome.
The first step taken in karyotype test is by taking a sample of your Mitosis cells. These samples can be taken from various tissues, including bone marrow, amniotic fluid, blood, or placenta. The sample is then placed in a laboratory dish that allows the cells to grow and multiply. Then the dividing cells are stopped in metaphase by treating it wit...
Klinefelter syndrome, although it can sometimes appear as an extremely uncomfortable and complicated condition, is nevertheless on that can be controlled, and to an extent, managed. This syndrome is relatively easy to diagnose, as the telltale sign that reveals the presence of Klinefelter is having two X chromosomes (ex. XXY), as opposed to a single X chromosome (ex. XY). Overall, this brings a person’s chromosome number to forty-seven, as opposed to the normal forty-six. Under a light microscope, a diagnosis can be made and delivered to the patient extremely quickly.
The horse that we know today developed from a small creature about the size of a small-dog, the fossil record of horses extend back to 50 million years ago. During evolution, some horses had survive tough conditions to breed the next generation this process known as natural selection. The horse developed into completely different animal from Hyracotherium also known as “Eohippus” meaning the “Darwin horse” to Equus, today's horses. Throughout the millions of years many changes had occurred to the evo-lution of horse, this essay will discuss the evolution of horses with the use of tayony, natural selection and modern research. When naming, describing, and classifying organisms including all animals, plants and microorganisms of the world, taxonomy is the right name used for this in science.