Trisomic and Allelic Differences Influence Phenotypic Variability During Development of Down Syndrome Mice

            Down syndrome is the result of one more or less copies of human chromosomes 21 where the occurrence is 1 of every 700-800 live births. Individuals experiencing Down syndrome display wide range of phenotypic characteristics (severities) which include facial dysmorphology, cognitive impairment, behavioral anomalies and congenital heart defects. Although these traits are specifically identified as typical for individuals with Down syndrome, however precise genetic and molecular mechanisms that causes these specific traits are not well understood. It has been thought that the trisomy of ‘Down Syndrome  critical/chromosomal region’ is responsible for most of the phenotypic traits of Down Syndrome however more researches have been conducted in mice in which prove that the ‘Down Syndrome critical/chromosomal region’ is in fact not sufficient to cause craniofacial features, a common characteristic of Down Syndrome.

            This experiment aims to prove how ‘Down Syndrome Critical/chromosomal region’ is not the only factor that causes the characteristics in individuals but genes of each individuals. Experimental mice from different genetic background, both experiencing Down Syndrome conditions were compared regarding the size of their mandible and craniofacial phenotypes. The first group of mice was a 'standard' Down syndrome mice since these specific groups are typically used in many if not all of experiments and trials concerning down syndrome. The second group of mice came from a mixed background. Mice that developed from mixed genetic background have a larger overall size of morphologically different mandible than the other mice. In addition, there were also in cerebellar and brain size and behavioural tests of learning and memory.These discoveries that have been found during myriad of mice with down syndrome shows that the differences may be due to genetic background difference. This experiment presents evidence that allelic differences in trisomic and nontrisomic genes as well as trisomc gene content all contribute to phenotypic differences shown in mandibular precursor development.

            All of the mice used within this experiment were bred for many generations to stabilize a certain trait and to exclude other possible traits that may affect development of that desired trait. The investigation as well focuses on the embryonic samples which had been implanted with Down Symdrome to explore size differences. From the embryo, RNA were extracted from the cells and through the techniques of PCR (polymerase chain reaction), amplification of DNA were rendered then examined. These two factors being investigated (embryonic samples and DNA) support the hypothesis of which allelic differeces in trisomic content and genetic background cause viariety in Down Syndrome phenotype such as differences in body size (pre and post natal), mandibular precursor.

            Within the experiment, mice from different genetic background were compared. Identical methodologies were used as well as same environmental conditions. These two factors would assure that no other factors would affect the development of each type of mice. The differences being presented within these mice were the size of mandibular precursors, size and volume of embryos, size of the brain and as well as each individual’s ability to learn. The hypothesis made in the beginning of this experiment has been proven to be correct.

Golden Rice, Golden Idea?

More than half of the population of the world depend on agriculture and harvests. Farming, however, is not as easy as it seems, it is prone to be attacked by many factors whether it was weather or pests. Droughts, floods or pests have the potential to entirely destroy crops. Scientists have been trying to counter these problems, but nature had always won the battle. Although these problems may seem inevitable, and perhaps even impossible to escape,  human kind had recently developed another solution, 'GMO' or genetically modified organisms. One famous example would be 'Golden Rice'. How exactly are these plants different?

Through the process of genetic 'cut and paste', scientists were able to transfer specific traits into crops that are popularly planted and consumed. Traits such as resistance to weather and pests are the main focuses. Golden rice, are able to survive through droughts or flooded condition for up to two weeks, their stems are stronger meaning they are less likely to collapse when heavy wind hits. Their stems are as well toxic for certain insects, making them pest resistant. Due to their effectiveness in survival and physical strength, golden rice increase crop production by up to 30 percent. Golden rice are also genetically modified to provide consumers with vitamin B which is crucial in health development. 

Personally, although GMO or specifically golden rice are very effective and can provide a huge solution to areas where nutrients are insufficient but is it really that safe? There have been many arguments regarding the safety of GMO products and golden rice, whether or not excess of nutrients could be dangerous. Golden rice claims to be pest resistant, of only certain species....if a species of pests attack, where Golden Rice is not resistant, then the effect would be severe and quick spreading. There are also researches discussing negative effects of golden rice on Monarch butterflies and the ecosystem in general. Again, effect on human's health have not been scientifically investigated.

Can it be dangerous for human consumers? Is it worth it? I believe further research must be done concerning human's health because if a disease do spread  among these plants then the effect would be too fast and simply too severe to solve.