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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.

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.

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.

Bipolar disorder is a common, complex genetic disorder, but the mode of transmission remains to be discovered. Many researchers assume that common genomic variants carry some risk for manifesting the disease. The research community has celebrated the first genome-wide significant associations between common single nucleotide polymorphisms (SNPs) and bipolar disorder. Currently, attempts are under way to translate these findings into clinical practice, genetic counseling, and predictive testing. However, some experts remain cautious. After all, common variants explain only a very small percentage of the genetic risk, and functional consequences of the discovered SNPs are inconclusive. Furthermore, the associated SNPs are not disease specific, and the majority of individuals with a "risk" allele are healthy. On the other hand, population-based genome-wide studies in psychiatric disorders have rediscovered rare structural variants and mutations in genes, which were previously known to cause genetic syndromes and monogenic Mendelian disorders.

The largest genome-wide association study to date, involving more than 300 institutions and more than 250,000 subjects, roughly doubles the number of known gene regions influencing height to more than 400. The study provides a better glimpse at the biology of height and offers a model for investigating traits and diseases caused by many common gene changes acting together.

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.

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.

Questions about the nature of viruses remain quite vexing. Recent studies of the giant Mimivirus illustrate this point. Its large size and correspondingly large genome test our general ideas of viruses as small, simple entities. The existence of genes associated with translation, metabolism, DNA repair, and protein folding raises questions about the evolutionary history of viruses. Further studies of this virus, and the search for other giant viruses, may shed light on these issues.

High heritability points to a major role for inherited genetic variants in the aetiology of schizophrenia7, 8. Although risk variants range in frequency from common to extremely rare9, estimates10, 11 suggest half to a third of the genetic risk of schizophrenia is indexed by common alleles genotyped by current genome-wide association study (GWAS) arrays. Thus, GWAS is potentially an important tool for understanding the biological underpinnings of schizophrenia

These case studies heralded a new appreciation for the phenomenon of genetic chimerism-when an individual carries two or more genetically distinct cell lines in different parts of her body. Until the advent of techniques for blood typing and karyotyping cells, genetic chimeras where thought to be very rare. They only came to light when the phenotypes associated with the two distinct genomes were so discordant that the resulting individual was clearly exceptional, with patches of distinct skin coloration throughout the body, for example, or hermaphroditic genitals. In reality, genetic chimeras may be quite common, disguised in perfectly normal bodies harboring genetically distinct cell lineages.

Exploratory data analysis and common statistical assumptions in biology