Environment and Experience Affect Gene Expression
One must consider multiple environments when considering influences on gene expression.(Lobo, 2008). Epigenetics explains how changes take place in the human organism for a variety of reasons, other than solely because of disease or genetic variations. Epigenetics explains how traits and diseases become heritable. Environmental experiences, especially stressful ones, can alter biological processes in later development and can affect an individual’s reactions to stimuli across the lifespan (Jacobson, 2009). Murgatroyd and Spengler (2011) explained how, through biological reactions to stress, children’s stress-regulating pathways and their emotional regulation systems are affected by chronically adverse living conditions. Further, these biological changes have the potential to alter future responses to stress.
Possessing a Gene and Vulnerability
Although an individual may posses a gene, he or she may not necessarily develop the disease ordinarily associated with the disease. Vulnerability is built upon a number of factors, which do not always provoke a disease process. Breedlove et al. (2010) explained that an individual can possess a gene, although it may or may not be expressed. A combination of environmental experiences and influences affect whether a gene is expressed in an individual. Factors include parenting style, social standing, socioeconomic status, and other life experiences (Jacobson, 2009). Other influences affect gene expression as well. The use of drugs and other substances such as alcohol, living conditions, geographic location, and environmental toxins can affect the development of diseases and conditions later in life (Breedlove, Watson, & Rosenzweig, 2010).
Ethical Considerations for Genetic Screening
Juengst (1997) made some interesting points about the ethics of genetic screening, such as the emotional and psychological affect of the testing, and whether effective preventive interventions are available after an individual completes the testing. Further, genetic testing can pathologize individuals because of self-stigmatization or social stigma attached to disease or its predisposition (Murgatroyd & Spengler, 2011).
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