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The goal of this project was to design and create a genetic construct that would allow for <br/>tumor growth to be induced in the center of the wing imaginal disc of Drosophila larvae, the <br/>R85E08 domain, using a heat shock. The resulting transgene would be combined with other <br/>transgenes in

The goal of this project was to design and create a genetic construct that would allow for <br/>tumor growth to be induced in the center of the wing imaginal disc of Drosophila larvae, the <br/>R85E08 domain, using a heat shock. The resulting transgene would be combined with other <br/>transgenes in a single fly that would allow for simultaneous expression of the oncogene and, in <br/>the surrounding cells, other genes of interest. This system would help establish Drosophila as a <br/>more versatile and reliable model organism for cancer research. Furthermore, pilot studies were <br/>performed, using elements of the final proposed system, to determine if tumor growth is possible <br/>in the center of the disc, which oncogene produces the best results, and if oncogene expression <br/>induced later in development causes tumor growth. Three different candidate genes were <br/>investigated: RasV12, PvrACT, and Avli.

ContributorsSt Peter, John Daniel (Author) / Harris, Rob (Thesis director) / Varsani, Arvind (Committee member) / School of Molecular Sciences (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
Speciation is the fundamental process that has generated the vast diversity of life on earth. The hallmark of speciation is the evolution of barriers to gene flow. These barriers may reduce gene flow either by keeping incipient species from hybridizing at all (pre-zygotic), or by reducing the fitness of hybrids

Speciation is the fundamental process that has generated the vast diversity of life on earth. The hallmark of speciation is the evolution of barriers to gene flow. These barriers may reduce gene flow either by keeping incipient species from hybridizing at all (pre-zygotic), or by reducing the fitness of hybrids (post-zygotic). To understand the genetic architecture of these barriers and how they evolve, I studied a genus of wasps that exhibits barriers to gene flow that act both pre- and post-zygotically. Nasonia is a genus of four species of parasitoid wasps that can be hybridized in the laboratory. When two of these species, N. vitripennis and N. giraulti are mated, their offspring suffer, depending on the generation and cross examined, up to 80% mortality during larval development due to incompatible genic interactions between their nuclear and mitochondrial genomes. These species also exhibit pre-zygotic isolation, meaning they are more likely to mate with their own species when given the choice. I examined these two species and their hybrids to determine the genetic and physiological bases of both speciation mechanisms and to understand the evolutionary forces leading to them. I present results that indicate that the oxidative phosphorylation (OXPHOS) pathway, an essential pathway that is responsible for mitochondrial energy generation, is impaired in hybrids of these two species. These results indicate that this impairment is due to the unique evolutionary dynamics of the combined nuclear and mitochondrial origin of this pathway. I also present results showing that, as larvae, these hybrids experience retarded growth linked to the previously observed mortality and I explore possible physiological mechanisms for this. Finally, I show that the pre-mating isolation is due to a change in a single pheromone component in N. vitripennis males, that this change is under simple genetic control, and that it evolved neutrally before being co-opted as a species recognition signal. These results are an important addition to our overall understanding of the mechanisms of speciation and showcase Nasonia as an emerging model for the study of the genetics of speciation.
ContributorsGibson, Joshua D (Author) / Gadau, Jürgen (Thesis advisor) / Harrison, Jon (Committee member) / Pratt, Stephen (Committee member) / Verrelli, Brian (Committee member) / Willis, Wayne (Committee member) / Arizona State University (Publisher)
Created2013
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Gene-centric theories of evolution by natural selection have been popularized and remain generally accepted in both scientific and public paradigms. While gene-centrism is certainly parsimonious, its explanations fall short of describing two patterns of evolutionary and social phenomena: the evolution of sex and the evolution of social altruism. I review

Gene-centric theories of evolution by natural selection have been popularized and remain generally accepted in both scientific and public paradigms. While gene-centrism is certainly parsimonious, its explanations fall short of describing two patterns of evolutionary and social phenomena: the evolution of sex and the evolution of social altruism. I review and analyze current theories on the evolution of sex. I then introduce the conflict presented to gene-centric evolution by social phenomena such as altruism and caste sterility in eusocial insects. I review gene-centric models of inclusive fitness and kin selection proposed by Hamilton and Maynard Smith. Based their assumptions, that relatedness should be equal between sterile workers and reproductives, I present several empirical examples that conflict with their models. Following that, I introduce a unique system of genetic caste determination (GCD) observed in hybrid populations of two sister-species of seed harvester ants, Pogonomyrmex rugosus and Pogonomyrmex barbatus. I review the evidence for GCD in those species, followed by a critique of the current gene-centric models used to explain it. In chapter two I present my own theoretical model that is both simple and extricable in nature to explain the origin, evolution, and maintenance of GCD in Pogonomyrmex. Furthermore, I use that model to fill in the gaps left behind by the contributing authors of the other GCD models. As both populations in my study system formed from inter-specific hybridization, I review modern discussions of heterosis (also called hybrid vigor) and use those to help explain the ecological competitiveness of GCD. I empirically address the inbreeding depression the lineages of GCD must overcome in order to remain ecologically stable, demonstrating that as a result of their unique system of caste determination, GCD lineages have elevated recombination frequencies. I summarize and conclude with an argument for why GCD evolved under selective mechanisms which cannot be considered gene-centric, providing evidence that natural selection can effectively operate on non-heritable genotypes appearing in groups and other social contexts.
ContributorsJacobson, Neal (Author) / Gadau, Juergen (Thesis advisor) / Laubichler, Manfred (Committee member) / Pratt, Stephen (Committee member) / Arizona State University (Publisher)
Created2012
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Noninvasive prenatal testing using cell-free fetal DNA (CffDNA) testing is a rapidly developing area in prenatal diagnosis. Fetal genetic testing can occur with a simple maternal blood sample, since CffDNA can be found in maternal plasma. Thus, no harm is caused to mother or fetus to obtain this genetic information,

Noninvasive prenatal testing using cell-free fetal DNA (CffDNA) testing is a rapidly developing area in prenatal diagnosis. Fetal genetic testing can occur with a simple maternal blood sample, since CffDNA can be found in maternal plasma. Thus, no harm is caused to mother or fetus to obtain this genetic information, providing significant benefits for those users. How the test should be integrated in existing prenatal programs has yet to be seen. CffDNA testing is an exciting technology and has attracted attention from many stakeholders, yet the lack of regulation and guidance has left legal, ethical, and social questions unanswered. This paper outlines a number of those issues expressed in the present literature on the matter.
ContributorsVeeder, Shaylynn Lee (Author) / Marchant, Gary (Thesis director) / Robert, Jason (Committee member) / Milleson, Valerye (Committee member) / Barrett, The Honors College (Contributor) / School of Social Transformation (Contributor) / School of Politics and Global Studies (Contributor) / Sandra Day O'Connor College of Law (Contributor) / Department of Psychology (Contributor)
Created2014-05
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Communication amongst eusocial insect is key to their success. Ants rely on signaling to mediate many different functions within a colony such as policing and nest mate recognition. Camponotus floridanus uses chemosensory signaling in the form of cuticular hydrocarbons to regulate these functions. Each cuticular hydrocarbon profile contains numerous hydrocarbons,

Communication amongst eusocial insect is key to their success. Ants rely on signaling to mediate many different functions within a colony such as policing and nest mate recognition. Camponotus floridanus uses chemosensory signaling in the form of cuticular hydrocarbons to regulate these functions. Each cuticular hydrocarbon profile contains numerous hydrocarbons, however it is yet to be seen if Camponotus floridanus can discriminate between linear hydrocarbons of similar length. Individual specimens were conditioned in three different ways: 5 conditioning with high concentration of sugar water (1;1 ratio), 1 conditioning with high concentration of sugar water, and 5 conditioning with low concentration of sugar water (1;4). Two linear hydrocarbons were use, C23 and C24, with C23 always being the conditioned stimulus. Specimens who were conditioned 5 times with high concentration of sugar water were the only group to show a significant response to the conditioned stimulus with a p-value of .008 and exhibited discrimination behavior 46% of the time. When compared 5 conditioning with high concentration to the other two testing conditioning groups, 1 conditioning with high concentration produced an insignificant p-value of .13 was obtained whereas when comparing it with 5 conditioning low concentration of sugar a significant p-value of .0132 was obtained. This indiciates that Camponotus floridanus are capable of discrimination however must be conditioned with high concentration of sugar water, while number of conditioning is insignificant.
ContributorsDamari, Ben Aviv (Author) / Liebig, Juergen (Thesis director) / Ghaninia, Majid (Committee member) / Pratt, Stephen (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2014-05
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The knowledge of medical genetics is currently used with prenatal testing, and the advancements in the field of behavioral genetics may someday allow for its use with prenatal testing as well. The use of prenatal procedures for medical phenotypes has its own implications and should these techniques be used for

The knowledge of medical genetics is currently used with prenatal testing, and the advancements in the field of behavioral genetics may someday allow for its use with prenatal testing as well. The use of prenatal procedures for medical phenotypes has its own implications and should these techniques be used for behavioral phenotypes, such implications can also apply. The complexity of behavior in terms of the factors that may affect it, along with the way it is conceptualized and perceived, adds further implications for prenatal testing of it. In this thesis, I discuss the qualitative, quantitative, and historical facets of prenatal testing for medical and behavioral phenotypes and the undercurrent of eugenics. I do so by presenting an example of the medical phenotype (cystic fibrosis) as a case for envisioning the implications of medical phenotypes before delving into examples of behavioral phenotypes (aggression, impulsivity, extraversion, and neuroticism) in order to explore the implications shared with those for medical phenotypes as well as those unique to it. These implications then set the foundation for a discussion of eugenics, and the considerations for how behavioral genetics with prenatal testing may give way to a modern form of it.
ContributorsMinai, Mandana (Author) / Maienschein, Jane (Thesis director) / Robert, Jason (Committee member) / Magnus, David (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor) / Department of Psychology (Contributor)
Created2014-05
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Olfactory discrimination tasks can provide useful information about how olfaction may have evolved by demonstrating which types of compounds animals will detect and respond to. Ants discriminate between nestmates and non-nestmates by using olfaction to detect the cuticular hydrocarbons on other ants, and Camponotus floridanus have particularly clear and aggressive

Olfactory discrimination tasks can provide useful information about how olfaction may have evolved by demonstrating which types of compounds animals will detect and respond to. Ants discriminate between nestmates and non-nestmates by using olfaction to detect the cuticular hydrocarbons on other ants, and Camponotus floridanus have particularly clear and aggressive responses to non-nestmates. A new method of adding hydrocarbons to ants, the “Snow Globe” method was further optimized and tested on C. floridanus. It involves adding hydrocarbons and a solvent to a vial of water, vortexing it, suspending hydrocarbon droplets throughout the solution, and then dipping a narcotized ant in. It is hoped this method can evenly coat ants in hydrocarbon. Ants were treated with heptacosane (C27), nonacosane (C29), hentriacontane (C31), a mixture of C27/C29/C31, 2-methyltriacontane (2MeC30), S-3-methylhentriacontane (SMeC31), and R-3-methylhentriacontane (RMeC31). These were chosen to see how ants reacted in a nestmate recognition context to methyl-branched hydrocarbons, R and S enantiomers, and to multiple added alkanes. Behavior assays were performed on treated ants, as well as two untreated controls, a foreign ant and a nestmate ant. There were 15 replicates of each condition, using 15 different queenright colonies. The Snow Globe method successfully transfers hydrocarbons, as confirmed by solid phase microextraction (SPME) done on treated ants, and the behavior assay data shows the foreign control, SMeC31, and the mixture of C27/29/31 were all statistically significant in their differences from the native control. The multiple alkane mixture received a significant response while single alkanes did not, which supports the idea that larger variations in hydrocarbon profile are needed for an ant to be perceived as foreign. The response to SMeC31 shows C. floridanus can respond during nestmate recognition to hydrocarbons that are not naturally occurring, and it indicates the nestmate recognition process may simply be responding to any compounds not found in the colony profile and rather than detecting particular foreign compounds.

ContributorsNoss, Serena Marie (Author) / Liebig, Juergen (Thesis director) / Pratt, Stephen (Committee member) / Haight, Kevin (Committee member) / School of Life Sciences (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
As a biology major, many of my classes have included studying the fundamentals of genetics or investigating the way genetics influence heritability of certain diseases. When I began taking upper-division psychology courses, the genetic factors of psychological disorders became an important part of the material. I was exposed to a

As a biology major, many of my classes have included studying the fundamentals of genetics or investigating the way genetics influence heritability of certain diseases. When I began taking upper-division psychology courses, the genetic factors of psychological disorders became an important part of the material. I was exposed to a new idea: that genes were equally important in studying somatic diseases as they were to psychological disorders. As important as genetics are to psychology, they are not part of the required courses for the major; I found many of my peers in psychology courses did not have a grasp on genetic fundamentals in the same way biology majors did. This was a disconnect that I also found in my own life outside the classroom. Growing up, my mother consistently reminded me to limit my carbs and watch my sugars. Diabetes was very prevalent in my family and I was also at risk. I was repeatedly reminded of my own genes and the risk I faced in having this biological disorder. However, my friend whose father was an alcoholic did not warn her in the same way. While she did know of her father's history, she was not warned of the potential for her to become an alcoholic. While my behavior was altered due to my mother's warning and my own knowledge of the genetic risk of diabetes, I wondered if other people at genetic risk of psychological disorders also altered their behavior. Through my thesis, I hope to answer if students have the same perceived genetic knowledge of psychological diseases as they do for biological ones. In my experience, it is not as well known that psychological disorders have genetic factors. For example, alcohol is commonly used by college students. Alcohol use disorder is present in 16.2% of college aged students and "40-60% of the variance of risk explained by genetic influences." (DSM V, 2013) Compare this to diabetes that has "several common genetic variants that account for about 10% of the total genetic effects," but is much more openly discussed even though it is less genetically linked. (McVay, 2015)This stems from the stigma/taboo surrounding many psychological disorders. If students do know that psychological disorder are genetically influenced, I expect their knowledge to be skewed or inaccurate. As part of a survey, I hope to see how strong they believe the genetic risk of certain diseases are as well as where they gained this knowledge. I hypothesize that only students with a background in psychology will be able to correctly assign the genetic risk of the four presented diseases. Completing this thesis will require in-depth study of the genetic factors, an understanding of the way each disease is perceived and understood by the general population, and a statistical analysis of the survey responses. If the survey data turns out as I expect where students do not have a strong grasp of diseases that could potentially influence their own health, I hope to find a way to educate students on biological and psychological diseases, their genetic risk, and how to speak openly about them.
ContributorsParasher, Nisha (Author) / Amdam, Gro (Thesis director) / Toft, Carolyn Cavaugh (Committee member) / Ostwald, Madeleine (Committee member) / Department of Psychology (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description

The purpose of the project is to create a survey that will be sent out to thousands of members of the Global Alliance for Genomics and Health (GA4GH) to update GA4GH's Catalogue of Genomic Data Initiatives online. GA4GH's Catalogue of Genomic Data Initiatives has not been updated in several years,

The purpose of the project is to create a survey that will be sent out to thousands of members of the Global Alliance for Genomics and Health (GA4GH) to update GA4GH's Catalogue of Genomic Data Initiatives online. GA4GH's Catalogue of Genomic Data Initiatives has not been updated in several years, leading to outdated and incorrect information. The survey will be used to gather information from genetic groups worldwide to update and increase the amount of data in the Catalogue on the GA4GH website. The questions were created in collaboration with GA4GH and the Human Pangenome Reference Consortium (HPRC). The actual survey was designed on Qualtrics.

ContributorsKapadia, Venus (Author) / Cook-Deegan, Robert (Thesis director) / Tsosie, Krystal (Committee member) / Barrett, The Honors College (Contributor) / Department of English (Contributor) / School of Music, Dance and Theatre (Contributor) / Department of Psychology (Contributor) / School of Life Sciences (Contributor)
Created2023-05
Description

This project is an investigation of the gene by environment (GxE) interactions’ effect on substance use outcomes among refugee communities. Substance use disorders (SUDs) are a major public health concern, affecting individuals and communities worldwide. The etiology of SUDs is complex, involving a combination of genetic, environmental, and social factors.

This project is an investigation of the gene by environment (GxE) interactions’ effect on substance use outcomes among refugee communities. Substance use disorders (SUDs) are a major public health concern, affecting individuals and communities worldwide. The etiology of SUDs is complex, involving a combination of genetic, environmental, and social factors. In recent years, there has been growing interest in the role of gene by environment interactions in the development of SUDs, particularly in vulnerable populations such as refugees. Refugee populations are exposed to a range of environmental stressors that may interact with genetic factors to increase their risk of SUDs. However, a number of studies describe a “refugee paradox,” where despite having been exposed to risk factors that can lead to SUDs, they are less likely to develop SUDs. Understanding these gene by environment interactions in refugee communities is crucial for not only understanding this phenomenon, but developing effective prevention and treatment strategies for this population. This thesis aims to investigate the gene by environment interactions underlying substance use in refugee communities and to analyze different methods for gene by environment analyses, ultimately determining which method is best suited for this population.

ContributorsEwais, Mariam (Author) / Sellner, Erin (Thesis director) / Su, Jinni (Committee member) / Barrett, The Honors College (Contributor) / School of Human Evolution & Social Change (Contributor) / Department of Psychology (Contributor) / School of Life Sciences (Contributor)
Created2023-05