Bethany V. Bowling

Genetic Literacy of Undergraduate Non–Science Majors and the Impact of Introductory Biology and Genetics Courses

ABSTRACT With the advancement of genetic information and technologies, there is an increasing need for a genetically literate public. This study looks critically at student learning and at the current instruction of genetics in introductory non–science major biology and genetics courses at the undergraduate level. A new diagnostic tool, the Genetic Literacy Assessment Instrument, was administered pre- and postcourse to more than 300 students in six introductory nonmajor courses that emphasize genetics to varying degrees. Current data from students in these courses show a precourse average score of 43 percent correct zn the inventory. Postcourse scores increased only modestly, to an average of 49 percent. In this article, we discuss the impact of teaching methods and course content on scores, as well as student learning in the different content areas of genetics. The results suggest that further studies in genetics education are needed to better understand the effect of teaching methods on achieving genetic literacy.

The Genome of Pseudomonas fluorescens Strain R124 Demonstrates Phenotypic Adaptation to the Mineral Environment

Microbial adaptation to environmental conditions is a complex process, including acquisition of positive traits through horizontal gene transfer or the modification of existing genes through duplication and/or mutation. In this study, we examined the adaptation of a Pseudomonas fluorescens isolate (R124) from the nutrient-limited mineral environment of a silica cave in comparison with P. fluorescens isolates from surface soil and the rhizosphere. Examination of metal homeostasis gene pathways demonstrated a high degree of conservation, suggesting that such systems remain functionally similar across chemical environments. The examination of genomic islands unique to our strain revealed the presence of genes involved in carbohydrate metabolism, aromatic carbon metabolism, and carbon turnover, confirmed through phenotypic assays, suggesting the acquisition of potentially novel mechanisms for energy metabolism in this strain. We also identified a twitching motility phenotype active at low-nutrient concentrations that may allow alternative exploratory mechanisms for this organism in a geochemical environment. Two sets of candidate twitching motility genes are present within the genome, one on the chromosome and one on a plasmid; however, a plasmid knockout identified the functional gene as being present on the chromosome. This work highlights the plasticity of the Pseudomonas genome, allowing the acquisition of novel nutrient-scavenging pathways across diverse geochemical environments while maintaining a core of functional stress response genes.

Retention of STEM majors using early undergraduate researchexperiences

An early undergraduate research program for rising sophomores and juniors at risk of leaving STEM degree programs is described. Students are paid a stipend to work part-time, at a maximum of twenty hours per week, as part of a research team. Faculty researchers are not financially compensated for working with students. The program successfully brings together STEM departments to target students who are at risk of leaving their major. Initial results demonstrate a positive influence of undergraduate research in retaining STEM majors and improvements in Student Assessment of Learning Gains. Future work, including institutionalization of the project, is discussed.

Analysis of a SNP linked to lactase persistence: An exercise for teaching molecular biology techniques to undergraduates

Recent experimental evidence indicates that the ability of adults to tolerate milk, cheese, and other lactose‐containing dairy products is an autosomal dominant trait that co‐evolved with dairy farming in Central Europe about 7,500 years ago. Among persons of European descent, this trait is strongly associated with a C to T substitution at a polymorphic site 13,910 bp upstream of the lactase gene. This mutation results in the persistent expression of lactase into adulthood enabling individuals carrying a T−13,910 allele to digest lactose as adults. In this report, we describe a laboratory exercise for an undergraduate molecular biology course in which students determine their own genotype at the −13,910 polymorphic site and correlate this with their ability to tolerate dairy products. The exercise is used as a tool to teach basic molecular biology procedures such as agarose gel electrophoresis, PCR 1 , and DNA sequencing. Students are actively engaged in the learning process, not only by analyzing their own DNA but also by applying their knowledge and skills to answer an authentic question. The exercise is also integrated with lecture material on the control of gene expression at the transcriptional level, in particular, how transcription factors can influence the activity of a promoter by binding to cis‐acting DNA regulatory elements located within the proximal promoter of a gene or distant enhancer regions. Biochemistry and Molecular Biology Education Vol. 39, No. 2, pp. 133–140, 2011

High school biology/life science teachers' presentation of genetic counseling and health care career options in their classrooms.

Studies show teachers play an influential role in the career decision-making process of students and early knowledge of genetic counseling (GC) increases the likelihood students will consider this career option. This quantitative study is the first to explore the presentation of GC and other health care career options by high school (HS) biology/life science (B/LS) teachers in their classrooms. Our findings indicate most B/LS teachers present GC as a career option to HS students, agree it complements classroom activities, and perceive students as interested in learning about the profession. However, teachers note many barriers to spending class time presenting GC careers. Consequently, a substantial number of teachers spent a minimal amount of time presenting health care careers in general. We discuss ways genetic counselors can enhance career resources, reduce barriers, and foster student interest in pursuing a career in GC by developing partnerships with HS B/LS teachers.

Bringing Next-Generation Sequencing into the Classroom through a Comparison of Molecular Biology Techniques.

Abstract Although the development of next-generation (NextGen) sequencing technologies has revolutionized genomic research and medicine, the incorporation of these topics into the classroom is challenging, given an implied high degree of technical complexity. We developed an easy-to-implement, interactive classroom activity investigating the similarities and differences between current sequencing methodology and three NextGen technologies. The activity uses existing materials created by each of the biotechnology companies that outline their instrumentation and chemistries. Following this activity, students will understand the molecular biology behind these NextGen applications and the similarities to existing Sanger sequencing methods.

Engaging Students in Natural Variation in the Introductory Biology Laboratory via a Statistics-Based Inquiry Approach

ABSTRACT Natural variation, including the continual selective pressures that lead to speciation, is one of the more dynamic aspects of biology. However, traditional instruction on the topic is often passive in nature, leaving little opportunity for scientific inquiry. In this laboratory exercise, we use a statistics-based, guided-inquiry approach to engage students in natural variation. Students are introduced to speciation and classification by using a dichotomous key to identify various common local trees on the basis of leaf characteristics. Once the students have learned characteristics useful for identification, they are given two leaf samples, a sugar maple and an “unknown.” They are asked to choose characteristics and collect quantitative data in order to determine whether the unknown is a sugar maple. Before data collection, students form hypotheses related to the identity of their unknown, followed by statistical comparison of means to support or refute their original hypotheses. In this way, students gain an appreciation for the activities undertaken by taxonomists that are related to natural variation and classification.