Lifelong Effects

This picture was taken from the following website:
http://www.lucinafoundation.org/assets/hydrocephalus.jpg

This past Sunday, October 10th, 2010, I watched a movie with my mom and sister at home on the Hallmark Channel called "Follow the Stars Home." It was produced in 2001 and starred Kimberly Williams-Paisley. It was aired from 4:45 - 7:00 pm. Essentially, the movie started out with a romantic love story between a couple who got together after meeting when the lady did some work for her future groom's brother. Before they knew it, they found out the wife (played by Williams-Paisley) was pregnant. After one of the sonograms, they received some bad news from the doctor. The baby was discovered to have genetic defects. The bad news was, unfortunately, only confirmed when the couple got a second opinion. Upon the wife's decision to keep the baby, her husband promptly left her, claiming he didn't want to have anything less than a perfect child. He wanted her to get an abortion as soon as they found out, but she decided to continue with the pregnancy. Before the child was born, the wife's brother-in-law (who introduced the couple and was also a doctor) did a further examination on the baby still in utero. He found the baby girl, if carried to full-term, would have fluid on the brain, also known as hydrocephalus (and pictured above), in addition to spinal cord and central nervous system damage, as well as poor development of the heart and lungs. Several surgeries would be needed to induce the development necessary for the baby's correct growth. She would not be able to walk, talk, and she would have a hard time breathing. Worst of all, though, her predicted life span was a mere six years. The movie went on to show the baby and her struggle throughout her life, as well as the constant and tedious way her mother and grandmother cared for her. Eventually, the drama re-entered the movie to add to the storyline, but a synopsis of the scientific part of the movie is given above.

I learned a lot from watching this movie. First, life is never easy. My eyes were opened to the role of parents when children are at such a young age. Even working with newborn babies at the hospital has not revealed this to me. It really made me think because, as a girl, I may be in that position one day, and it caused me to ponder about what I would do if this situation occurred later in my life. The last decision is ultimately left up to me because the baby would be growing in my body, but should my opinion on this sort of issue interfere with my marriage? If so, what is the cut-off point where things should only get my opinion as compared to my husband's? If not, where do you draw the line as to what really should be considered fairly in a marriage, concerning the birth of the first child? This relates to our class, of course, because it is a genetic disease, although it was never named specifically, that affected the physical and mental development of the child. A mutation somewhere in the process of fertilization and cleavage caused a child's life to end significantly earlier than her peers. Previously in class, we also discussed some of the ethical issues that come with certain diseases -- an issue that was brought up by the viewing of this movie. I'm really glad I watched this movie, and it was nice for me to see that the things we are learning in class really do relate to life outside the classroom.

Cytoplasmic Bridges

The picture above was taken from the following website:
http://www.mc.vanderbilt.edu/histology/word/2004/
Cell%20Junctions%2004.htm

One term in our textbook that was unfamiliar to me is "cytoplasmic bridges." This term is defined as the "continuity between adjacent cells that results from incomplete cytokinesis during gametogenesis." There are cytoplasmic connections between the dividing cells during meiosis. Cytoplasmic bridges, however, are the product of meiotic cell divisions that help daughter cells remain connected. Above is a picture detailing exactly where cytoplasmic bridges can be found, connecting actin filaments.

The information referenced above was taken from the following reference: Gilbert, Scott F. "The Saga of the Germ Line - Meiosis." Developmental Biology. Vol. 9. Sunderland, MA: Sinauer Associates, 2010. 599. Print.

Reflection



This picture was taken from the website: http://2.bp.blogspot.com/_tqy4jJBa2DM/
TFg2JlPtefI/AAAAAAAAAYw/qaaEGkupGzc/s1600/thinking-outside-the-box.jpg

 I love being in this class for the sole reason that I feel like I am finally learning something useful. This is the point at which we have enough foundational knowledge from core concepts to apply it what we encounter in the everyday world. My future career goal is to be a pediatrician, so it is very important to me to learn about developmental diseases, how the develop, why they occur, and how they can be treated. What better class to cover all these topics? Learning about gametogenesis and the difference between mitosis and meiosis in males and females has also helped me in my Genetics class. I am able to understand, now, why mutations occur, as well as the effect they have on an individual. It is nice to learn about an entire concept, especially through the use of two classes. I learn best by writing things down, which includes both visual and audio learning. Taking notes and doing the various assignments for this class, especially since they have been in paper format up to this point, have been very helpful for me. I am working on incorporating other learning styles into my learning, but this has worked for me so far because this is what I have encountered. The two most important things I have learned about so far are spermatogenesis and oogenesis. Understanding how, when, and why these processes take place is key to understanding the development of some diseases, as well as the seeing the large number of mutations that can occur along the way. The ethical side of these processes becomes confusing for me, especially concerning genotypes of individuals. If there is a mutation somewhere in development and an individual ends up with three alleles instead of two, I am still confused as to how society should treat this person, mainly with isues concerning their personal rights. I need to study this more on my own to decide on these issues and take a clear stance on them. This class has opened my eyes to the world around me. Individuals with physical disabilities now peak my interest rather than scare me because of the nature of their disease and how it developed. It automatically becomes a new research project. This has opened my eyes to my future as well. A lot of individual research time will benefit me because I will no longer be ignorant to these issues. I will, instead, be aware and informed of them.

Down Syndrome and Mutations




This picture was taken from the following website:
https://cornellbiochem.wikispaces.com/file/view/
downsyndrome1.jpg/66756907/downsyndrome1.jpg

 
Recently in class, we have been talking about mutations. We were assigned to do a project on a specific disease, and I chose to do mine on Down syndrome. This is an abnormality caused by nondisjunction in fertilization, or the failure of homologous chromosomes to separate as they should during reproduction, resulting in an extra copy of a chromosome. This is a mutation in the sense that, normally, only two chromosomes would develop in a zygote, whereas three chromosomes develop with this syndrome. A picture of a child with Down syndrome is posted above.

One of our class textbooks, "Mutants" by Leroi, describes two noteworthy details about mutations. First, our faces seem to be the most vulnerable body part in displaying mutation's effects (Leroi). This was apparent to me because one of my sources for my project was MedLine Plus, an online journal. On this website, symptoms of Down syndrome are listed, but nearly all of them are facial disfigurements. It describes an abnormally shaped head, a flattened nose, separated brain sutures, small ears, a small mouth and upward slanting eyes (MedLine Plus). Also, it stated that Down syndrome is mainly apparent to doctors at birth because of its distinct physical abnormalities (MedLine Plus). I had noticed this during my project, but as I read from my textbook, it became more apparent to me. So my question is this: why are our faces so vulnerable to mutation? What about our faces makes mutations almost attract the area? Is there a genetic reason for this? Does the environment play a role?

The other detail Leroi suggests in his coverage of mutations is that "more than 70% of spontaneously aborted fetuses bear severe chromosomal abnormalities" (Leroi). Leroi adds, "it is now widely supported that miscarriage is an evolved device that enables mothers to screen for, and rid themselves of, genetically impaired progeny." Also while doing my project, I found that it was very common for mothers to have abortions, or miscarriages, after they got positive results from testing their babies for Down syndrome. If more than half of spontaneous abortions occur because of genetic abnormalities, such as the one that causes Down syndrome, why does it not account for fetuses with this anomaly? This suggests that spontaneous abortion must have sort of a "cut-off point," in which it can no longer occur. If not, at least some of these fetuses would have spontaneously aborted, especially more than enough to allow Down syndrome to be the "most common single cause of human birth defects" (MedLine Plus). This also peaked my interest. We have answers to the more basic questions concerning spontaneous abortion, such as how and why it happens, but we still do not have all the answers. When does it take place during the pregnancy? Does it stop after a certain point? Are there other criteria? Does the mother have to have specific qualities that allow this process to continue in her? Or is it normally built in to every female? Does it stop after the female reaches a certain age?

These questions, along with those above have yet to be answered and are useful for more research in the scientific world.

The book "Mutants" is a scientific book written in 2003 by Armand Marie Leroi as a means of finding a "direct way into the human genome and the human body" through the discovery of mutants. Leroi is an evolutionary developmental biologist, and thus, has ample experience and knowledge to write such a book. It is informative and does not take sides. Rather, it seeks to provide a new way of thinking: all humans are mutants, not merely those with severe physical disfigurements that we may more often assume. This is, therefore, a trustworthy source.

The other source I used is from an online, peer-reviewed, scientific, medical journal, and as such, does not give a specific author's name. The website is the following: http://www.nlm.nih.gov/medlineplus/ency/article/000997.htm and again, the source is informative. It does not take sides, but merely seeks to inform the public, or whoever may read this journal, of the symptoms of this disease. This website is a service of the United States National Library of Medicine, and the National Institutes of Health. Therefore, all the information posted on this site are reviewed by individuals of appropriate authority in terms of knowledge on the subject. This also, therefore, is a trustworthy source.

Cleft Palate

This picture was taken from the following website:
http://news.wustl.edu/news/Pages/20173.aspx

This past Sunday, September 12, I had the unfortunate task of attending the funeral of a close family friend. While it was slightly expected, death always seems to come at an unfortunate time, and it proved very hard for all the close family members. One of the people who spoke had an especially hard time. This was partly due to the fact that he had been given the task of speaking at his friend's funeral, however, the tears shed did not help. As he continued to speak, however, it was noticeable why he had such a hard time speaking, as well as why it was so hard to understand him. He had a cleft palate. This led to his slight speech impediment, as well as resulting in the slight difficulty others had when understanding him. After some research, I found the following information.

"We all start out life with a cleft lip and palate. During normal fetal development between the 6th and 11th weeks of pregnancy, the clefts in the lip and palate fuse together. In babies born with cleft lip or cleft palate, one or both of these splits failed to fuse." A cleft palate is a split or separation in the oral cavity. This is one of the most common birth defects, and affects about one in 1,000 babies. Children born with this disorder have struggles with eating, breathing and speaking. The cause of this anomaly is unknown, although genes and environment are suspected precursors. Surgeries provide the best results for treating clefts, however complications may be lifelong, such as they were in my encounter.

More than anything else, my eyes were opened to the social detriments birth defects can cause, even at the mature adult stage. At the funeral, even after this person had become an adult, it was apparent to the audience that something was wrong. It is hard to comprehend how such a small abnormality, that doesn't even have a known cause yet, can cause so much potential damage. Birth defects, in particular, are hard for me to understand because babies have done nothing to deserve them. We should be in constant appreciation of the fact that God has truly created our bodies more intricately than we will ever know.

The information in the second paragraph was taken from the following website: http://www.entnet.org/HealthInformation/cleftLipPalate.cfm.

Teratogens

The above picture was taken from the following website: 
http://www.learn.ppdictionary.com/prenatal%20development.htm

This week in class, we were discussing developmental anatomy. Along with the normal developmental anatomical structures, we discussed developmental abnormalities. A new word I learned while learning about these abnormalities was "teratogens." The word is derived from the Greek and literally translates to "monster-formers." Teratogens are the "exogenous agents that cause disruptions in development, resulting in teratogenesis, or the formation of congenital defects. Teratology is the study of birth defects and of how environmental agents disrupt normal development." Teratogens are substances, such as alcohol, drugs, hormones, cigarettes, lead mercury and radiation, that cause developmental, anatomical abnormalities. Above is a picture showing the different types of teratogens and their possible harmful effects on the fetus during development.


The information referenced above was taken from the following reference: Gilbert, Scott F. Developmental Anatomy - Medical Embryology and Teratology." Developmental Biology. Vol. 9. Sunderland, MA: Sinauer Associates, 2010. 28. Print