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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.

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.

 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.

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.

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.

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.

That's why a paper published Thursday in the journal Genetics in Medicine is so remarkable. The paper identifies NGLY1 deficiency as an inherited genetic disorder, caused by mutations in the NGLY1 gene. The researchers have confirmed eight patients with these mutations who share several symptoms, including developmental delays, abnormal tear production and liver 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.

Autism is rooted in genetics, including the mutation of certain genes that result in a failure of neurons in the brain to properly connect. Based on earlier genetic research funded by Autism Speaks, such as the Autism Genome Project (AGP), scientists have discovered some of these genes. But much more gene discovery needs to take place. The Autism Genome 10K Project will mark a substantial leap forward on this journey. The Autism Genome 10K Project builds on the successes of Autism Speaks' Autism Genetic Resource Exchange program (AGRE), a high-quality collection of more than 12,000 DNA samples from families affected by autism. The AGRE program has facilitated many high-impact scientific discoveries in recent years, including the risk genes discovered by the AGP and other researchers. With BGI sequencing the full complement of 10,000 samples collected by AGRE and collaborators in China, Autism Genome 10K leverages BGI's cutting-edge expertise and globally unrivaled capacity for high-quality genome sequencing.

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.

Although Hardy-Weinberg equilibrium is a fundamental part of introductory biology classes, students often have difficulty understanding its implications. This interrupted case study places students in the role of small teams who are conducting preliminary research into the impact of roads on the population structure of timber rattlesnakes in order to apply for a grant for further research. Research groups consisting of 3-4 students work through a series of questions allowing them to use HWE principles to discover for themselves how deviations from HWE can have implications for conservation biology. Periodic interruptions with help sheets (see Supplemental Materials) allow teachers to maintain an active role in the students' progress, while also demonstrating the collaborative nature of scientific research. Ultimately students formulate formal emails summarizing and interpreting their findings in order to "apply" for the grant. The case is designed for undergraduate students in introductory biology or in lower-level population genetics/conservation courses where connecting basic genetic principles to ecology and sustainability is key.

"CRACKING THE CODE"/"Cloning Paper Plasmid" activities can (1) serve as a review of the "genetic code" and the role it plays in our life; and, (2) to help students see how genes may be manipulated for genetic research, namely, gene cloning/genetic engineering. The laboratory time, the specialized equipment and expertise to carry out recombinant DNA experiments may be lacking in the high school. Activity 2 will help students conceptualize the mechanics involved in cutting and ligating DNAs into a plasmid vector with "sticky ends" of complementary DNA base pairs.

Over the past few decades, genetic research has revealed two deep truths about people. The first is that all humans are closely related-more closely related than all chimps, even though there are many more humans around today. Everyone has the same collection of genes, but with the exception of identical twins, everyone has slightly different versions of some of them. Studies of this genetic diversity have allowed scientists to reconstruct a kind of family tree of human populations. That has revealed the second deep truth: In a very real sense, all people alive today are Africans.

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

The STAR-G Project has put together fact sheets about disorders commonly screened for by newborn screening. The fact sheets were written specifically for families that have received an initial diagnosis of one of the disorders and want to know more general information. They address issues and answer questions that are of particular concern to parents. Each fact sheet was written by a genetic counselor and reviewed by metabolic and genetic specialists.

Even if you look like your mother, an innovative study suggests that not only humans but, in fact, all mammals are genetically more like Dad. We inherit equal amounts of genetic material from each parent, yet that coming from our father's side is more likely to take action, according to the study that was published in the journal Nature Genetics.

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.

curricular unit on Genetic Research

"Bioethics is the study of ethical, legal, and social issues raised by advances in biology and medicine. Bioethics addresses a range of controversial topics, including privacy and fairness in the use of genetic information, integration of new technologies, such as genetic testing, into medical practice, and the design and conduct of research studies and clinical trials.  "