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This interrupted case is based on a genome wide association study (GWAS) that identified the genetic variation causing some inhabitants of the Solomon Islands to have blond hair. The case illustrates the connection between genotype and phenotype, and an application of Hardy-Weinberg equilibrium. The narrative focusses on John and his new roommate, Peter, from the Solomon Islands who happens to have dark skin and blond hair. Using thought-provoking questions students learn about the genetics and the biochemistry of the hair color trait and how a single genetic variation can influence phenotype. Is migration or mutation involved?  Upon completion of the activity students will know the source of the genetic variation that causes the blond hair phenomenon in the Solomon Islands and if it has any European origins. The case was written for an upper-level genetics course, but could also be adapted for introductory biology or for a genetics course for non-majors. An optional PowerPoint presentation with clicker questions is available for download from within the Answer Key.

This interrupted case study for the flipped classroom applies evolutionary genetics research to human health. Students learn about a naturally occurring, but rare, allele of the CCR5 gene, CCR5-Δ32, which provides resistance to HIV. They use data from primary literature sources to predict and interpret worldwide patterns of CCR5-Δ32 frequency distribution. They then discuss how these allele frequency patterns may have been driven by selection imposed by various diseases or by other evolutionary mechanisms. Next, they test published data using Hardy-Weinberg equilibrium to examine if CCR5-Δ32 also provides genetic resistance to West Nile virus. Finally, they complete a jigsaw discussion of Nature News articles that report on how CCR5 research is being used to develop therapies to treat HIV. Originally written for the evolution portion of a yearlong biology series for undergraduate majors, the case is also appropriate for some non-majors biology courses or, with added complexity, upper-level evolution, genetics, or cell biology courses.

The origin of viruses remains mysterious because of their diverse and patchy molecular and functional makeup. Although numerous hypotheses have attempted to explain viral origins, none is backed by substantive data. We take full advantage of the wealth of available protein structural and functional data to explore the evolution of the proteomic makeup of thousands of cells and viruses. Despite the extremely reduced nature of viral proteomes, we established an ancient origin of the "viral supergroup" and the existence of widespread episodes of horizontal transfer of genetic information. Viruses harboring different replicon types and infecting distantly related hosts shared many metabolic and informational protein structural domains of ancient origin that were also widespread in cellular proteomes. Phylogenomic analysis uncovered a universal tree of life and revealed that modern viruses reduced from multiple ancient cells that harbored segmented RNA genomes and coexisted with the ancestors of modern cells. The model for the origin and evolution of viruses and cells is backed by strong genomic and structural evidence and can be reconciled with existing models of viral evolution if one considers viruses to have originated from ancient cells and not from modern counterparts.

There are a significant number of genetics curriculum resources designed by different companies, curriculum development outlets, state curriculum designers and individual teachers. What resources are good? How do you know? As part of the Geneticist-Educator Network of Alliances (GENA) Project, a Curriculum Content Review Committee was formed to review readily available classroom resources about patterns of inheritance. Click here to see original evaluation form used by the committee and here to see the summary of the committee's review.

18 min video- Ten thousand years ago, corn didn't exist anywhere in the world, and until recently scientists argued vehemently about its origins. Today the crop is consumed voraciously by us, by our livestock, and as a major part of processed foods. So where did it come from? Popped Secret: The Mysterious Origin of Corn tells the story of the genetic changes involved in the transformation of a wild grass called teosinte into corn.  Evidence from genetics supports archeological findings pinpointing corn's origins to a very particular time and place in Mexico

In this directed case study students follow a nurse practitioner and work with a diagnostics team to determine what is wrong with Tristan, an infant who comes to the clinic with multiple bruises. Students are given background and patient history, and are then given results of various blood tests ordered by the diagnostics team. The exercise emphasizes the physiological process of coagulation and the importance of various clotting factors, especially factor VIII. Students will be introduced to results from several blood tests, including: complete blood count, partial thromboplastin time, prothrombin time, metabolic panel, and factor VIII assay. The patient is ultimately diagnosed with severe hemophilia A and the case then introduces students to this disorder, the genetic determinants, the incidence, and ways to manage the disease. The data in this case are real and the story represents the medical history of an actual patient. Originally developed for pre-nursing students, this activity would also be suitable for majors in physiology or pre-medical students; it could also be used in an introductory genetics or biology course.

This case study follows a young cystic fibrosis (CF) patient named Lucas. Through Lucas's story and interactions between his parents and pediatrician, students learn about the scientific background and basis of CF. By reviewing email correspondence between Lucas's parents and various doctors, students gain an overview of CF research. CF has become a model disease in certain undergraduate biology classrooms due to its relatively clear mechanism and genetic basis. This case asks students to come up with their own ideas to improve on an existing line of research - gene therapy - in treating CF. During the process, students will gain a better appreciation of the innovative nature of science and develop research skills such as finding, understanding and analyzing primary literature. The activity was originally designed for first- and second-year students as part of an extracurricular case competition, but may be used for any undergraduate biology level. The case assumes basic (high school level) knowledge of genetics, biochemistry, cell biology and physiology.

This case study presents the story of Phil, an undergraduate majoring in biology, whose Russian cousin Dimitri has contracted tuberculosis (TB) from inmates at the prison where he works.  Phil learns that his cousin's failure to complete his antibiotic regimen likely contributed to the evolution of antibiotic-resistant TB in his body.  Phil consults with his friend Stacy, and together they try to understand Dimitri's condition by applying what they are learning in their genetics lab experiment about the role of random mutation in bacterial evolution (including the development of antibiotic resistance) through Luria- Delbrück fluctuation analysis. The same analysis includes calculation of the mutation rate, which Phil realizes is sufficient to cause MRSA and other antibiotic-resistant infections. This case study was originally developed for concurrent use in freshman/sophomore-level genetics, elementary statistics, and precalculus. However, it is also very appropriate for courses in introductory biology, evolutionary biology, and biostatistics. The teaching notes discuss various ways to run the case depending on the mathematics and biology background of students.

All living humans originated from populations of ancestors who migrated out of Africa less than 100,000 years ago. Learn how scientists have used genetic markers to trace the migration routes and origins of modern human populations.

About GeneCards®: GeneCards is a searchable, integrated database of human genes that provides comprehensive, updated, and user-friendly information on all known and predicted human genes. GeneCards extracts and integrates gene-related data, including genomic, transcriptomic, proteomic, genetic, clinical, and functional information. This is automatically mined from >100 carefully selected web sources, thereby allowing one-stop access to a very broad information base. GeneCards overcomes barriers of data format and heterogeneity, and uses standard nomenclature and approved gene symbols. It presents a rich subset of data for each gene, and provides deep links to the original sources for further scrutiny. GeneCards is widely used, and assists in the understanding of gene-related aspects of biology and medicine.

This case study follows purveyors of peas, Joel E. and Jolene Greengiant, as they learn about the origin, biochemistry, genetics and eventual artificial selection of sweet (wrinkled) peas, all in the context of evolutionary biology. This integrative approach employs both problem-based learning techniques and directed questions as students engage in a series of modules. 

The possibilities of pseudo-peptide-DNA mimics like PNA (peptide nucleic acid) having a role for the prebiotic origin of life prior to an RNA world is discussed on the basis of literature data showing that this type of molecules might have formed on the primitive earth (or other places in the universe), as well as data indicating the possibilities of template-directed PNA chemical replication and ligation. In particular, the merits of an achiral prebiotic genetic material is discussed.

The study by researchers from the Wellcome Trust Sanger Institute and collaborators at La Trobe University in Melbourne and several other Australian institutes, challenges a previous theory that suggested an influx of people from India into Australia around 4-5 thousand years ago. This new DNA sequencing study focused on the Y chromosome, which is transmitted only from father to son, and found no support for such a prehistoric migration. The results instead show a long and independent genetic history in Australia.

Researchers have now created the first molecules of RNA, DNA's singled-stranded relative, that are capable of copying almost any other RNAs. The discovery bolsters the widely held view among researchers who study the origin of life that RNA likely preceded DNA as the central genetic storehouse of information in the earliest cells some 4 billion years ago.

HIV jumped from apes to humans at least four times, as evidenced by genetically distinct groups of the virus that have been detected: M, N, O, and P. While N and P have had little impact, M is responsible for the pandemic affecting millions of individuals, and O has infected another 100,000.

A stride to understand the cancer and move towards its prevention, this time experts from around the world involved in searching the genome of cancer have analyzed the mutational signatures, the processes of mutation in the DNA of cells (which are always in the origin of cancer) and they follow a fixed pattern.

How did viruses evolve? Are they a streamlined form of something that existed long ago, or an ultimate culmination of smaller genetic elements joined together?

This site provides biochemical methods and computer tools to allow students to use their own DNA "fingerprints" as a starting point in the study of human evolution. Two experiments are currently available, which are supported by reagents and ready-to-use kits available from Carolina Biological Supply Company.

A complete understanding of evolution requires knowledge that spans many biological sub-disciplines. However, students are often taught evolution in the context of ecological systems and isolated from genetic and cellular ones. To address this issue, we have developed case studies that track the evolution of traits from their origination in DNA mutation, to the production of different proteins, to the fixation of alternate macroscopic phenotypes in reproductively isolated populations.

Origins of life with self-replicating molecules