Thawing the Frozen Shoulder

https://openriver.winona.edu/urc2018/1120/thumbnail.jp

Molecular, bioinformatic and statistical approaches to identify genes underlying complex traits in livestock

One of the primary goals for molecular geneticists working with livestock species is to identify and characterize genes underlying complex traits, the so-called quantitative trait loci (QTL). The primary strategy for identifying QTL involves several steps, one being fine mapping of a previously defined chromosomal region and another being identification of candidate genetic polymorphisms that may cause differences in phenotype. The studies presented in this dissertation address fine mapping methodology, use of the candidate gene approach for directly identifying candidate genetic polymorphisms and use of bioinformatic tools for identifying genetic polymorphisms in silico. Results from simulation studies suggest that two linkage disequilibrium-based fine mapping methods, one using haplotype information, the other using single marker information, provide QTL position estimates with comparable accuracy. Additional research is necessary to determine optimal fine mapping methods under experimental research conditions. The candidate gene studies presented, concerning the porcine connexin 37 (CX37) and bone morphogenetic factor 15 (BMP15) genes, highlight use of comparative sequence and biological information for identifying candidate genetic variants. Two synonymous mutations were discovered in the CX37 gene, which was subsequently mapped to SSC6 q24--31. However, these mutations were not significantly associated with fertility traits as hypothesized. Unfortunately, mutations could not be identified in BMP15, which was physically mapped to SSCX p11--13. Bioinformatic tools are shown here to be lucrative for identifying putative single nucleotide polymorphisms (SNPs) from redundant expressed sequence tag (EST) information in the pig. Using computer-derived SNPs, a correlation of 0.77 (p \u3c 0.00001) was found between the frequency of human and porcine SNPs in the coding regions (cSNPs) of 25 genes, while a correlation of 0.48 (p \u3c 0.0005) was found between the frequency of human and mouse cSNPs in 50 genes. This strong human-pig relationship should be verified in a larger sample so that SNP identification in pigs could be expedited by screening porcine genes homologous to human genes known to be SNP-dense in their coding regions. By capitalizing on statistical, bioinformatic and molecular tools in an integrated approach, the rate at which QTL are identified in livestock could be increased

In Order to Live

This portfolio, In Order to Live, includes some of the poetry and creative nonfiction pieces I wrote as a Creative Writing Minor at Cedarville University. “Printmaking” was published in the June 2015 edition of Spry, and “Deep Creek Lake” will be published in the summer anthology of Snapping Twig. The collection aims to redeem memory and salvage the sermon from previous experiences. I wrote about fingerprints, worms, grand pianos, the trinity, heartbreak, cancer and so much more to understand why any of it matters, in order to live

Three Essays on the Economics of Education

This dissertation is comprised of three essays on the economics of education. The first and third chapters examine marijuana legalization and its effects on students, while the second chapter examines the impact of pension incentives on teacher quality.The first chapter examines the extent to which there are negative spillovers of recreational marijuana legalization on underage marijuana use and educational outcomes. I use two complementary identification strategies that rely on plausibly exogenous spatial and temporal variation in access to marijuana in Oregon. In November of 2014, Oregon passed Measure 91, a referendum to legalize recreational marijuana. Unlike other legal states, Oregon allowed counties that voted against the legalization measure by at least 55% to opt out. Difference-in-differences estimates suggest that self-reported access to marijuana from the Oregon Student Wellness and Oregon Healthy Teens surveys did not change in counties above versus below the vote-share threshold after legalization, but that use increased, particularly for 11th-grade girls. Additionally, using data on high schools from the Oregon Department of Education, I find that chronic absenteeism, dropout rates, and English proficiency all get worse after legalization. The second chapter, which is co-authored with Patten Priestley Mahler, studies the impact of pension incentives on teacher quality by analyzing a return-to-work policy in North Carolina that effectively removed the push incentives embedded in teacher pensions by allowing them to tap into their pension while teaching. Using administrative public-school data from the North Carolina Research Data Center, we estimate the impact of teachers who returned to work after retirement on student outcomes. We develop an instrumental variable identification strategy centered on the cancellation of the policy and find small improvements in both reading and math achievement for students in the same school who had one of these teachers in their grade during the policy relative to students who did not. The results suggest that schools are losing effective teachers because of pension incentives and that return-to-work policies may be a way to retain them. The final chapter estimates the effect of recreational marijuana legalization on educational outcomes using exogenous spatial variation in access to marijuana dispensaries in Washington. In November 2012, Washington passed Initiative-502, a referendum to legalize recreational marijuana. As part of the initiative, the state capped the number of dispensaries at 334. It held a lottery to assign licenses in localities where the number of license applicants exceeded the local dispensary quota, thus generating exogenous variation in dispensary locations. Using an instrumental variable strategy and data on public high schools from Washington\u27s Office of Superintendent of Public Instruction, I find that schools near open dispensaries have worse chronic absenteeism, dropout rates, and discipline rates relative to schools near dispensaries that did not open. This is consistent with the negative effects of legalization that I estimate for Oregon in the first chapter