Saturday 29 March 2014

Alkaptonuria By: Saidia Ali

Alkaptonuria

By: Saidia Ali 

We are currently studying the genetics unit and we all know the basics now. In the beginning of this unit we learned about karyotypes and non-disjunction. All the information related to that will be useful in understanding this disorder better. So, get ready to learn about alkaptonuria! 

Alkaptonuria also called AKU and black urine disease  is a very rare genetic disorder that occurs because of a mutation in chromosome 3. Alkaptonuria is an inherited recessive disorder which means that it must be passed on by both parents. People who have one copy of the gene are carriers of the disease and do not suffer from it but there is a twenty-five percent chance of them passing it to their offspring. We know this because we have done Punnett square problems related to similar situations. 

Now that we know some basic information about the inheritance of alkaptonuria but what exactly is it? Alkaptonuria is a disorder caused by the lack of an enzyme homogentisic dioxygenase (HGD). Patients who have alkaptonuria are unable to break down a substance called homogentistic acid. As a result this acid starts to build up in the body leading to many severe problems which we will discuss later on. Patients with this disease are also unable to metabolize the amino acids called phenylalanine and tyrosine. These two amino acids are important in producing hormones and pigments. As I've mentioned before, alkaptonuria is a rare disease and it is estimated that it affects one out of 200,000 worldwide. In some countries AKU is more common like in Slovakia and the Dominican Republic where it affects one in every 19,000. AKU is not a disease that is only inherited by men or women, it is a disease that affects men, women, and children equally. AKU patients have a normal life expectancy. 











                                                                                                                                                     







  

Sometimes there are diseases where the patients cannot feel or see the symptoms but a patient with AKU can see the problems. Here is a list of the symptoms: 

  • One of the earliest signs in a baby are dark stains in his/her diaper.
  • Urine turning black or brown when exposed to air is a common symptom
  • Stained cartilage in the ear 
  • Darkening of skin
  • Arthritis in knees, back, and/or hips
The buildup of HGD can lead to heart problems. 























When AKU is suspected here are ways to diagnose the patient. One way is gas chromatography which is used to check for homogentisic acid in the urine. DNA testing can also be done to look for the mutated gene.
 Although there is no particular treatment for AKU there are ways to lower the symptoms and keep the disease from getting out of control. Many doctors recommend exercising and physiotherapy to assist the patient with arthritis. Maintaining a healthy diet is also key. Evidence shows that increasing the input of vitamin C can decrease the development of arthritis. Another crucial change in an AKU patient's diet is eliminating food that contain phenylalanine and tyrosine. These foods include meats, soy, nuts and seeds, and artificial sweeteners. 

Learning about this topic was very interesting and I hope that you enjoyed learning about this topic just as much as I did researching it.

Question: Do you think genetic engineering will help us find a cure for alkaptonuria in the future? Why or why not?



http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3108520/
















Surrogate Mothers by Uday Bakili

Surrogate Mother 

Uday Bakili 


          What is a surrogate mother anyway ? It is a female who carries the child of a another couple or person. One can't really call this "mother" a type of technology, because it is in fact a human being. But rather, the technology used to get the child to grow and exist in a mother, whose genetic makeup won't even affect the child. The technology being used is actually called artificial insemination using Intrauterine insemination. 

       Surrogate mothers is a very beneficial technology for people who have fertility problems, because of many varying reasons. Individuals who desperately want children and cannot get them, see this technology as a very useful alternative. The invention of this technology wasn't by a single person, but rather by the contribution of many people. In 1944, John Rock fertilized the first human ova outside the uterus, this lead to first surrogate mother in 1985, which has been continuing on till today.

 Surrogate mothers work by artificially getting sperm cells injected into their uterus. Mothers, get fertilized and grow the baby inside of them for the full duration of the 9 months. So, far it has been a very successful treatment with a 85 percent success rate.

As all good things have flaws so do surrogate mothers, there are many problems that might arise. The most common, is that their could be problems getting the surrogate mother fertilized, or the child could have genetic defects due to flawed genetics. The more common problem is that some surrogate mothers, don’t want to let the baby go, after it is born. 

Some ethical issues with this technolgy is that some parts of society believe that only a mother has the right to have her own child. They believe that it is improper to have a mother who is only raising the child for the payment of it.

 In the future, I think that scientists should worry less about the technological aspect of this, but more on the choice of the mother. Some mothers wish not to give the baby away, and scientists should pick women that are completely certain they 




































Reference : 
http://en.wikipedia.org/wiki/Surrogacy
http://www.surrogatemothers.com/
http://www.fertilityconsultants.ca/
http://www.surrogatemother.com/
http://www.ehow.com/about_4574417_surrogate-mothers.html

Tuesday 25 March 2014

Carbon-Capturing Plants by: Miss Dhaliwal

Climate change is the one of the most serious issues faced by the world today. The emission of greenhouse gases from factories, vehicles, and other sources has increased the overall temperature of the planet. The changes in temperature have resulted in extreme weather patterns, droughts, rising sea levels, spread of disease, and mass extinctions. Scientists worldwide are looking for solutions to heal the damage caused by human activity. One such solution involves generating transgenic plants to reduce the amount of greenhouse gases in the atmosphere.

Current chart and data for atmospheric CO2
Concentration of Atmospheric Carbon Dioxide


    Carbon dioxide is one of the most abundant greenhouse gases in the atmosphere. It is released primarily by the combustion of fossil fuels. The acceptable concentration of CO2 in the atmosphere is 350 parts per million (ppm); however, this upper limit has been exceeded since 1988. In 2013, the concentration of CO2 exceeded 400 ppm. In an effort to reduce the amount of CO2 in the atmosphere, scientists have proposed the idea of developing carbon-sequestering plants.

Carbon sequestered in soil by trees.
    Plants naturally utilize CO2 in the process of photosynthesis. Scientists hope to genetically alter plants, such as trees, to take up carbon dioxide from the atmosphere and store it in the soil. The sequestered carbon would increase soil fertility and it would remain in the soil for millennia. As of yet, bioengineered super carbon plants are still in development. Once produced, these plants would be used worldwide to reduce the amount of CO2 in the atmosphere, thereby alleviating climate change.

    As with all genetically engineered plants, there are concerns that these plants may alter natural ecosystems. Increasing carbon content of soil may have unforeseeable effects on natural wildlife. There are also concerns among conservative individuals who feel that one should not modify nature. However, I believe that these plants would be a tremendous blessing for this planet. If carbon emissions continue at an exponential rate, as they have been doing since the early 1900’s, climate change will cause mass extinction of the human species, as well as other species on this planet. These plants would prevent a major environmental collapse, and would aid in the recovery of this planet.

    How do you think the global population will react once carbon-sequestering plants are planted worldwide?

References:
http://co2now.org/
http://www.eurekalert.org/pub_releases/2010-10/aiob-gat092810.php
http://bioscience.oxfordjournals.org/content/60/9/742.full.pdf+html
http://arxiv.org/ftp/arxiv/papers/0804/0804.1126.pdf
http://www.forestsforever.org/Climate_Crises-Clearcutters_Hop_on_Cap_&_Trade.html
Blog written by Ms. Dhaliwal.