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Genetic studies of human disease are more challenging to perform in sub-Saharan Africa because genetic diversity is greater than in other populations. This pilot will increase our understanding of African genome variation and enable the design of large-scale genetic association studies in the region. Studies into the genetic basis of disease in European populations have made major advances in the past few years, yet similar studies in sub-Saharan Africa have been slower to develop. The high level of genetic diversity that exists in populations from sub-Saharan Africa makes genetic associations with disease more difficult to identify. The African Genome Variation Project aims to collect essential information about the structure of African genomes to provide a basic framework for genetic disease studies in Africa.

Middle and high school students need an opportunity to construct evidence-based explanations for how variation and natural selection can lead to adaptation of populations over time (NGSS MS-LS4-4 and HS-LS4-4). However, managing a population of classroom-friendly living organisms that consistently grow, develop, and thrive while students observe variation among individuals can be a real challenge.

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 interactive case discussion was created to emphasize the clinical relevance of population genetics, but is also a suitable resource for teaching the basic principles of population genetics while relating them to human genetic variation. Our understanding of human genetic variation has deepened over the past decade due to fine-scale genome mapping. Applying this knowledge to the evaluation of ancestry-based genetic testing strategies, such as direct-to-consumer genetic testing, is an important component of the practice of culturally-competent medicine and a relevant way to teach the foundations of population genetics, including Hardy-Weinberg equilibrium.

"Survival of the Fittest: Variations in the Clam Species Clamys sweetus" is a guided inquiry. This series of hands-on activities complements the HHMI DVD Evolution: Constant Change and Common Threads and requires simple materials such as M&Ms, Reese's Pieces, food storage bags, and paper cups. This activity has been designed to engage students in thinking about the mechanism of natural selection by encouraging them to formulate questions that can be answered through scientific investigation, data collection, and pattern recognition.

The life science/biology course is divided into 12 instructional segments grouped into four sections. In the first section, From Molecules to Organisms: Structures and Processes, students develop models of how molecules combine to build cells and organisms (IS1 [Structure and Function]; IS2 [Growth and Development of Organisms]; IS3 [Organization for Matter and Energy Flow in Organisms]). In the second section, Ecosystems: Interactions, Energy, and Dynamics, students zoom out to the macroscopic scale to show how organisms interact (IS4 [Interdependent Relationships in Ecosystems]; IS5 [Cycles of Matter and Energy Transfer in Ecosystems]; IS6 [Ecosystem Dynamics, Functioning, and Resilience]; IS7 [Social Interactions and Group Behavior]). Students return to the role that DNA plays in inheritance during the third section, Heredity: Inheritance and Variation of Traits (IS8 [Inheritance of Traits]; IS9 [Variation of Traits]). The class ends tying together interactions at all these scales by explaining evolution and natural selection in Biological Evolution: Unity and Diversity (IS10 [Evidence of Common Ancestry and Diversity]; IS11 [Natural Selection]; IS12 [Adaptation and Biodiversity]). A vignette in IS12 illustrates the level of three-dimensional understanding students are expected to exhibit as a capstone of the course.

Mutations and genetic variation

A powerful tool called pVAAST that combines linkage analysis with case control association has been developed to help researchers and clinicians identify disease-causing mutations in families faster and more precisely than ever before. The researchers describe cases in which pVAAST (the pedigree Variant Annotation, Analysis and Search Tool) identified mutations in two families with separate diseases and a de novo or new variation in a 12-year-old who was the only one in his family to suffer from a mysterious and life threatening intestinal problem.

NIH Genetic Variation Activity- Are you susceptible? Dice rolling game to model cardiovascular risk. -pdf for handouts

This directed case study was developed in order to present genomic data to students, allow them to interpret the impact of genetic variations on phenotype, and to explore precision medicine. Students are introduced to "Josie," a college sophomore who decides to have her genome sequenced after learning about genome-wide association studies (GWAS) in class. As students work  through the case, they learn about the different technologies that can be used in GWAS studies and interpret Josie's results for a subset of genetic markers that affect a range of traits from pharmacogenetics to disease risk alleles and non-pathogenic traits. Students are confronted with ethical issues such as duty to inform, actionable results, and variants of unknown significance (VUS). Students are also asked to reflect on their feelings about getting genomic testing for themselves. An optional activity for advanced students (included in the teaching notes) involves using the Gene database at NCBI to explore variants of the CYP2C9 gene. The case study is appropriate for use in undergraduate genetics or molecular biology classrooms.

This case is an exploration of the process of natural selection using white clover (Trifolium repens) as an example. In general, two forms of white clover can be found around the world in various habitats. One type is able to produce cyanide in its leaves, while the other is not. This variation within the clover species, along with the fact that cyanide production is paired with the production of a white stripe on the leaf, is used to teach the process of evolution through natural selection. 

The 1000 Genomes Project is an international collaboration to produce an extensive public catalog of human genetic variation, including SNPs and structural variants, and their haplotype contexts. This resource will support genome-wide association studies and other medical research studies. The genomes of about 2500 unidentified people from about 25 populations around the world will be sequenced using next-generation sequencing technologies. The results of the study will be freely and publicly accessible to researchers worldwide. Further information about the project is available in the About tab. Information about downloading, browsing or using the 1000 Genomes data is available in the Data tab.

Pharmacogenomics holds the promise that drugs might one day be tailored to your genetic makeup. By Mayo Clinic Staff Modern medications save millions of lives a year. Yet any one medication might not work for you, even if it works for other people. Or it might cause severe side effects for you but not for someone else. Your age, lifestyle and health all influence your response to medications. But so do your genes. Scientists are working to match specific gene variations with responses to particular medications.

Genetic differences among ethnically diverse individuals are largely due to structural elements called copy number variants (CNVs), according to a study published today (August 6) in Science. Compared with other genomic features, such as single nucleotide variants (SNVs), CNVs have not previously been studied in as much detail because they are more difficult to sequence. Covering 125 distinct human populations around the world, geneticist Evan Eichler at the University of Washington in Seattle and an international team of colleagues studied the genomes of 236 people-analyzing both SNVs and CNVs. "The take-home message is that we continue to find a lot more genetic variation between humans than we appreciated previously," Eichler told The Scientist.

A data collection and analysis lesson that examines selection for coat color in pocket mouse populations on different color substrates over time.

Researchers have made dramatic inroads into the study of polygenic and other complex human diseases, due in large part to knowledge of the human genome sequence, the generation of widespread markers of genetic variation, and the development of new technologies that allow investigators to associate disease phenotypes with genetic loci. Although polygenic diseases are more common than single-gene disorders, studies of monogenic diseases provide an invaluable opportunity to learn about underlying molecular mechanisms, thereby contributing a great deal to our understanding of all forms of genetic disease.

Why did you get the flu this winter, but your co-workers didn't? The answer, according to a new study of twins, may have less to do with your genes and more to do with your environment-including your past exposure to pathogens and vaccines. Our immune system is incredibly complex, with diverse armies of white blood cells and signal-sending proteins coursing through our veins, ready to mount an attack on would-be invaders. Everyone's immune system is slightly different-a unique mixture of hundreds of these cells and proteins. But the main driver of this variation is unclear. Although scientists know that our immune system can adapt to our environment-that's why vaccines work, for instance-it is also built by our genes.

The mouse is the leading organism for disease research. A rich resource of genetic variation occurs naturally in inbred and special strains owing to spontaneous mutations. However, one can also obtain desired gene mutations by using the following processes: targeted mutations that eliminate function in the whole organism or in a specific tissue; forward genetic screens using chemicals or transposons; or the introduction of exogenous transgenes as DNAs, bacterial artificial chromosomes (BACs) or reporter constructs. The mouse is the only mammal that provides such a rich resource of genetic diversity coupled with the potential for extensive genome manipulation, and is therefore a powerful application for modeling human disease.

In the animal kingdom, humans are known for our big brains. But not all brains are created equal, and now we have new clues as to why that is. Researchers have uncovered eight genetic variations that help determine the size of key brain regions. These variants may represent "the genetic essence of humanity," says Stephan Sanders, a geneticist and pediatrician at the University of California, San Francisco, who was not involved in the study. These results are among the first to come out of the ENIGMA (Enhancing Neuro Imaging Genetics through Meta-Analysis) collaboration, involving some 300 scientists from 33 countries. They contributed MRI scans of more than 30,000 people, along with genetic and other information, most of which had been collected for other reasons. "This paper represents a herculean effort," Sanders says.

Genomics resources for teachers, from state of Michigan. This website includes three main sections: Family History- which looks into genomics at the organism level Multifactorial Traits- which looks into genomics at the cellular and gene level Genetic Variation- which looks into genomics at the molecular level