In this paper, I aim to accentuate the correlation between individuals diagnosed with Schizophrenia and poverty. Though I am fortunate enough to say that no member of my family has been diagnosed with Schizophrenia, over the course of my high school career my interest in working in the medical field introduced me to patients that have. Living in the outskirts of Los Angeles where poverty affects the lives of numerous individuals, drug abuse is not something that is uncommon. Guillermo, whose name has been replaced with another in this paper, was twenty-two years of age when he was diagnosed with Schizophrenia. Immigrant to the United States from Guatemala at the age of fourteen, his journey to the states forced him to endure physical and mental abuse. When Guillermo arrived to the United States and resided with family in California, he was exposed to substances that his family believes are what led him to develop symptoms that align to those of Schizophrenia. Unable to ground himself financially, drugs were amidst the few things that relieved him of his “failures” time after time. The last time I spoke with Guillermo, he blamed the lack of money and the conditions he was living in for his state of being. A few months into my first semester in college and my biology lecture introduced me to the effect epigenetics has on gene expression. Guillermos case highlights the fact that just as there are biological reasons why one develops a disease, one can also arise from environmental factors that have drastic effects on one’s wellness. Schizophrenia, in this paper, will be addressed not only through genetics but also through environmental factors that have the potential to contribute to the development of Schizophrenia.
Schizophrenia, like all mental disorders, takes a toll on diagnosed patients. Not only are individuals negatively affected, but families and friends must learn to adapt and meet the needs of those that have been diagnosed. Schizophrenia, according to the Diagnostic and Statistical Manual of Mental Disease, is a “chronic brain disorder that affects less than one percent of the U.S. population” (. Though commonly heritable, social factors and exposure to drug abuse early in life have the ability to lead to the development of Schizophrenia, a brain disorder that has been categorized as a psychosis disorder (U.S. National Library of Medicine). In other words, individuals diagnosed with Schizophrenia experience a disconnect from reality through means of hallucinations (i.e, auditory, the most common, visual, and tactile), delusions, decreased ability to perform in social settings as well as experience tremors, facial tics, rigidity and slow movement (U.S. National Library of Medicine).
Although Schizophrenia is commonly heritable, scientists are still unsure of the direct cause that leads to this mental disorder. A deletion syndrome, referenced as 22q11.2, has been associated as one of the causes of Schizophrenia. Over the course of the past decade, scientists have discovered that rare chromosomal arrangements such as duplication, deletion, inversion and translocation of DNA have made impactful contributions to variation in the human genome (Foley et al., 2017). These chromosomal arrangements have led to neurodevelopmental disorders. Though it was already known that mutations like deletion could have a drastic impact on gene expression, technological advances have accentuated the amount of deletions and duplications present in patients diagnosed with Schizophrenia. In turn, this allows scientists to conclude that regulation of transcription of DNA is important in the translation of genes (Foley et al., 2017).
Scientists have linked schizophrenic symptoms to neurodevelopmental etiology. Given that molecular etiology of a disease is a direct link to drug discovery, the discovery of brain changes associated with function, structure, and neurochemicals has led to one medication as a form of treatment. Since Schizophrenia cannot be cured but can be treated, antipsychotic medication that targets a dopamine receptor, dopamine D2 receptor, has been known to minimize the probability of a patient relapse, in some but not all cases. (Foley et al., 2017). According to Foley, antipsychotic medication, however, “have little impact on debilitating behavior and cognitive defect and overall illness outcomes have not been improved” (Foley et al., 2017). In other words, antipsychotic medication can alleviate symptoms but have shown no progression towards curing the illness. This, in turn, has led scientists to target receptors like the dopamine D2 receptor. Affecting almost one percent of adults, the Large-Scale Genome Wide Association conducted a study that focused on single nucleotide polymorphisms, SNPs, that have a known predictability across the human genome.
Testing single nucleotide polymorphisms frequency between patients with Schizophrenia to those that do not allowed scientists to localize genes that can play a critical role in the development of Schizophrenia. By comparing cases to controls, scientists were able to note differences between individuals with schizophrenia to those that did not. According to the large-scale genome wide association one-hundred and eight loci were identified as target genes to optimize treatment (Foley et al., 2017). One challenge that researchers have come to encounter is that since Schizophrenia is a clinical diagnosis, it is difficult to develop treatments because it is not know which individuals will grow up to develop Schizophrenia to those that will not. Hence, if there is no pool of individuals to analyze, in order to observe change of the disease and the effect Schizophrenia has on the individual, it becomes a challenge to create treatments tailored to a population.
Furthermore, amongst these loci, the major histocompatibility complex (MHC) that spans across four megabases of chromosome 6 has a linked association to the development of Schizophrenia. The histocompatibility complex codes for approximately more than four hundred genes that are crucial to immune function (Foley et al., 2017). Through Polygenic Risk Score, a method used to test alleles, assays were conducted to test for critical at-risk alleles. The location of alleles in chromosomes could be a contributor as “the soma [neuron cells] contains the nucleus, which in turn contains the genetic material in the form of chromosomes” (Boeree). The New York Times asserts, “He’d need a bone-marrow transplant to survive. After the procedure came the miracle . . . Somehow the transplant cured the man’s Schizophrenia” (Velasquez-Manoff, 2018). The article further says, “These symptoms probably result from the immune system attacking the central nervous system or from a more generalized inflammation that affects how the brain works” (Velasquez-Manoff, 2018). Consequently, the connection that doctors have made in this case allude to the central nervous system. Interestingly, alterations in myelin, made of sheath and insulate nerve fibers that remain as the main constituent of white matter, is known to have defects in neurons and the central nervous system. These defects in neurons and the central nervous system relate to the neuropsychiatric disease (Swaminathan, 2007). Given that the central nervous system uses the aid of myelin to complete its given purpose, in order to develop proper brain development, receptors need neuregulin 1.