Principles of Genetics and Genomics
Question 1
A lot of people have mentioned that genetic disorders can ‘hide’ for generations due to natural selection if the genes are recessive, meaning requiring two copies of the affected gene for the disease to appear. Natural selection occurs when some genetically-determined trait becomes more or less common in the wild because it survives better or worse in the environment than previously (Hartl, 2014). That is, if the feature does poorly, then it isn’t passed into the next generation, and eventually dies out. If the feature does well, it continues and shows up more often. Some genetic disorders are dominant: neuropathy and an autoimmune disorder are examples. Autoimmune disorders are born if the body tends to put in more effort in reinforcing its defensive mechanism against dangerous substances, including infection, toxic, and allergen, that make it unable to defend itself from its intruders. While neuropathy is a common shorthand for peripheral neuropathy, which means the nerves in your body are unable to function properly. Only one copy of an affected dominant gene is needed to cause these disorders: a person with that gene has the disorder, and will pass on the condition to half their children (statistically speaking). Sometimes, two copies of the dominant gene (one from each parent) can be fatal. However, most people (80%) with neuropathy and an autoimmune disorder do not inherit the relevant gene: it is the result of random mutation (the gene involved is at the end of Chromosome 4: the ends of chromosomes are particularly prone to damage and change). Other disorders may be epigenetic (requiring a trigger), which may or may not be known. Since these do not automatically affect everyone with the gene, they can be passed on to children. Some disorders only become fatal after the reproductive years. Often, the affected person is unaware of the problem until they are older, although they may have cumulative damage throughout their life. Such genetic information is coded and stored in chemical form by long nucleic acid sequences called “genes” (in most organisms the storage molecule is DNA), and that that occasional variations in this DNA give rise to variation between individuals of any given species. You can include evolution by noting that evolution occurs by nature of selecting the most fit from among the variants in the said population.
Question 2
The main difference between mutation, migration, selection, and genetic drift typically is that mutations tend to increase the diversity of genetics, whereas the other ten to reduce it. Genetic drift, as well as natural selection, usually enhances the genetic difference within a given population; on the other hand, migration homogenizes the genetic variation; thus, reducing the population’s disparities. Genetic drift, also known as the Sewall Wright effect, is an evolutionary force that acts along with mutation, natural selection, and migration (Harland & Grainger, 2011). This force results in the variation of allele frequencies of a population at random directions (unpredictable results), mainly caused by random events such as a natural disaster. Genetic drift is a population-level phenomenon. It is nothing more than a sampling error. Given a starting allele frequency, smaller populations are more likely to deviate from there than larger populations. Migration elsewhere is another factor where a section of the individuals migrates out to establish a new colony in a different environment. The migration can happen due to various reasons: survival, epidemics, natural calamity, overpopulation, conflict, among others. The migrated population over generations of time is expected to differ from their parental population in a variety of traits, or gene frequencies. Mutation is considered to be chemical or physical DNA changes in a person. This can be random changes that occur in a DNA sequence: it could be due to copying error.
Question 3
Some people will have the same eyes, hair, and any habits like their family members. The same thing may happen in the case of diseases. This occurs through the genes. Genes influence our possibilities of having a few regular sicknesses, similar to like neuropathy and an autoimmune disorder, but so do many other factors, such as diet and lifestyle (Korf, 2011). The greater part of the genes are from guardians and work similarly as it does for the guardians. But sometimes, a gene is not a perfect copy. There may be some changes. Such changes within the genes are referred to as mutations. A condition arising from the genes of mutations in the genetic disorder/ Simply, Genetics gives a possibility into developing a certain disease. Also, environmental factors are essential. Family history is vital to understanding the likelihood of having some diseases like diabetes, cancer, or chromosomal diseases. Moreover, the way we live our life is made according to the prescription your genes possess. The instructions given by the DNA are the basic code of life. We are breathing, eating, being stressed, or more keen to do certain things because our genes knew how to let us do these.
References
Hartl, D. L. (2014). Essential genetics: A genomics perspective. Jones & Bartlett Publishers.
Harland, R. M., & Grainger, R. M. (2011). Xenopus research: metamorphosed by genetics and genomics. Trends in Genetics, 27(12), 507-515.
Korf, B. R. (2011). Genetics and genomics education: the next generation. Genetics in Medicine, 13(3), 201-202.