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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.

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.

Genetic research is leading to the development of more genetic tests that can be used for the diagnosis of genetic conditions. Genetic testing is available for infants, children, and adults. Genetic tests can be used to diagnose a disease in an individual with symptoms and to help measure risk of developing a disease. Adults can undergo preconception testing before deciding to become pregnant, and prenatal testing can be performed during a pregnancy. Results of genetic tests can help physicians select appropriate treatments for their patients.

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.

She says people became much more willing to talk about their genetic predispositions and seek out testing for conditions like Alzheimer's disease and cystic fibrosis. The number of patients seeking genetic counseling and testing has increased dramatically, according to a 2014 study that looked at how Jolie's announcement affected interest in testing. But the number of genetic counselors, the people who help both doctors and patients make sense of these tests, hasn't expanded enough to keep up with that demand. There are just 4,000 certified genetic counselors in the country today. That's one for every 80,000 Americans.

I'm a carrier of a Jewish genetic disease. With that, here's my journey, which will explain why I'm so passionate about advocating for JScreen-a national organization that focuses on education and screening for Jewish genetic diseases.

After her two children were diagnosed with a rare genetic condition, Sharon Terry dedicated her life to creating systems-level solutions that will alleviate burdens for consumers and build opportunities for them to be empowered in their own health care. She is the CEO of Genetic Alliance, an international non-profit organization, now in its 25th year, that is the world's largest network of health related organizations working from a consumer perspective. Genetic Alliance builds capacity within the genetics and health community by forging novel partnerships, promoting informed decision-making, and sharing individual, family, and community perspectives.

This case study is designed to teach basic concepts of genetics by focusing on a rare disease, pseudoxanthoma elasticum (PXE).  Chromosome 16 is the narrator at the beginning of the case and introduces students to genes, chromosomes and mutations. The focus then shifts to the patient and his mother as she finds out about her son's disease and her subsequent efforts to connect with patient advocacy groups for support. The case concludes with students watching a TED talk given by Sharon Terry, the real-life mother on whom this story is loosely based, so that students can connect on an emotional and human level with someone who has intimate experience as a parent of children with a rare genetic disease. The case is suitable for high school general biology classes, but it can also be used by biology major or non-major undergraduates in a lower-division biology class, or in any lower-division non-major class focused on human disease.

In a unique twist on human genomics studies that seek to identify genetic variants linked to human disease, researchers have combined whole-exome sequencing of 50,726 adults with the individuals' long-term electronic health record (EHR) data. The effort, by researchers at the Geisinger Health System in Pennsylvania and Regeneron Genetics Center, a subsidiary of New York-based Regeneron Pharmaceuticals, has yielded novel disease-linked variants, including loss-of-function alleles. The team behind the project, called DiscovEHR, has also found that about one in 30 of the individuals harbors a deleterious genetic variant for which a screen or treatment already exists. The group's analysis is described in two papers published today (December 22) in Science.

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.

 In one of the first successful attempts at genetically engineering mosquitoes, HHMI researchers have altered the way the insects respond to odors, including the smell of humans and the insect repellant DEET. The research not only demonstrates that mosquitoes can be genetically altered using the latest research techniques, but paves the way to understanding why the insect is so attracted to humans, and how to block that attraction. "The time has come now to do genetics in these important disease-vector insects.

webquest with student group members assuming different roles when investiigating genetic disease 

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.

The external environment's effects upon genes can influence disease, and some of these effects can be inherited in humans. Studies investigating how environmental factors impact the genetics of an individual's offspring are difficult to design. However, in certain parts of the world in which social systems are highly centralized, environmental information that might have influenced families can be obtained. For example, Swedish scientists recently conducted investigations examining whether nutrition affected the death rate associated with cardiovascular disease and diabetes and whether these effects were passed from parents to their children and grandchildren (Kaati et al., 2002). These researchers estimated how much access individuals had to food by examining records of annual harvests and food prices in Sweden across three generations of families, starting as far back as the 1890s. These researchers found that if a father did not have enough food available to him during a critical period in his development just before puberty, his sons were less likely to die from cardiovascular disease. Remarkably, death related to diabetes increased for children if food was plentiful during this critical period for the paternal grandfather, but it decreased when excess food was available to the father. These findings suggest that diet can cause changes to genes that are passed down though generations by the males in a family, and that these alterations can affect susceptibility to certain diseases. But what are these changes, and how are they remembered? The answers to questions such as these lie in the concept of epigenetics.

Dogs are excellent models for studying genetics, especially disease genetics. Work done in the last 20 years has shown that dogs share many gene-related disorders with people. Each breed is a closed reproductive population with distinct rates of heritable diseases, which dramatically increases the odds of finding disease-related loci. In creating new dog breeds, we reduce the gene pool within those populations, and fix many alleles. This homogeneous background makes it much easier to map QTLs and perform linkage analyses

This video excerpt from NOVA examines the dilemma some people face when they are deciding whether to undergo genetic testing. Journalist Catherine Elton describes her decision to refuse a test for BRCA1, a mutation that signals an increased risk of breast and ovarian cancers, despite the history of disease in her family. The video also explains that genetic testing results can help some individuals improve their wellness, prevent the onset of diseases they are at risk for, or lessen the harmfulness of diseases they do contract.

The Rare Disease Foundation is focussed on linking basic science and clinical practice to increase the efficiency of rare disease research. This model is called Translational Care. This model drives patient based, treatment focussed research projects from disease characterization to treatment with greater efficiency. By incorporating research, astute clinician observation and parental knowledge into the various stages of rare disease research we impact the speed of discovery and the way rare conditions are managed.

Genetic tests are now available to look for specific heritable diseases like Huntington's, assess your risk of developing conditions like heart disease, and more. Learn about four different types of genetic testing and take our poll. Would you take these tests yourself?

Parkinson's is a result of the loss of cells in various parts of the brain, including one portion that produces the neurotransmitter dopamine. Dopamine is essential for being able to move in a coordinated way, so the loss of dopamine causes the tremors often associated with the condition. While the exact cause of Parkinson's is unknown, genetics and environment are contributing factors. Most cases occur in patients with no family history of Parkinson's disease, but there are 13 gene mutations that have been linked to either causing the disease or increasing one's risk of developing it. Certainly not everyone who carries these gene mutations develops Parkinson's, but identifying these genetic indicators is the beginning of developing more precise treatments.

Although genetic factors contribute to congenital heart disease, many children born with heart defects have healthy parents and siblings, suggesting that new mutations that arise spontaneously -- known as de novo mutations -- might contribute to the disease. New research shows that about 10 percent of these defects are caused by genetic mutations that are absent in the parents of affected children.