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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.

I learned that gene expression is the process by which the information of genes is used to direct the function of cells. Gene expression is regulated in all cells because not all genes are needed all the time or under all circumstances. For example, brain cells need to express certain genes that are not needed in muscle cells, and muscle cells need to express certain genes that are not needed in brain cells. Likewise, bacteria need to express different genes depending on the availability of food and other aspects of their surroundings.

Such descriptions of GMOs raises fears about whether gene transfer between species is outside of how evolution operates and therefore unnatural. Research, however, has repeatedly shown the opposite to be true. In May 2015, researchers showed that practically every known species of cassava (sweet potato) contained genes from Agrobacterium, a bacterial species whose genes we have also harnessed to create other GM crops. The genes were inserted over 8,000 years ago and may have helped the tuber evolve into its current, edible form. This phenomenon of genetic transfer during evolution between species, also known as 'horizontal gene transfer' is not restricted to plants.

This 8-minute video is derived from the 2013 Holiday Lectures on Science. In it, Dr. Charles Sawyers explains the difference between proto-oncogenes, oncogenes, and tumor suppressor genes, and how mutations in these genes drive cancer development. "Cancer genes" can affect several cellular processes that he groups into three categories: cell growth and survival (i.e., genes involved in the cell cycle, cell fate (i.e., genes involved in cell differentiation), and genome maintenance (i.e, genes involved in DNA repair.)

At first, the researchers assumed that genes would shut down shortly after death, like the parts of a car that has run out of gas. What they found instead was that hundreds of genes ramped up. Although most of these genes upped their activity in the first 24 hours after the animals expired and then tapered off, in the fish some genes remained active 4 days after death.

The study is the first to examine all of the gene networks affected by fructose that result in changes to brain function and metabolism-more than 20,000 genes in total. Although the study was conducted using rats, the researchers report that the majority of the sequenced genes are comparable to those in humans, including more than 200 genes in the hippocampus, a brain area crucial to memory, and 700 in the hypothalamus, the seat of the brain's metabolic control center.

When life emerged on Earth about 4 billion years ago, the earliest microbes had a set of basic genes that succeeded in keeping them alive. In the age of humans and other large organisms, there are a lot more genes to go around. Where did all of those new genes come from? Carl Zimmer examines the mutation and multiplication of genes.

In population genetics, gene flow (also known as gene migration) is the transfer of alleles or genes from one population to another. Migration into or out of a population may be responsible for a marked change in allele frequencies (the proportion of members carrying a particular variant of a gene). Immigration may also result in the addition of new genetic variants to the established gene pool of a particular species or population.

Quintana-Murci and his colleagues also took advantage of a previously published map of areas of the human genome where Neanderthal genes are present, showing that innate immune genes are generally more likely to have been borrowed from Neanderthals than genes coding other types of proteins. Specifically, they noted that 126 innate immune genes in present-day Europeans, Asians, or both groups were among the top 5 percent of genes in the genome of each population most likely to have originated in Neanderthals. The cluster of toll-like receptor genes, encoding TLR 1, TLR 6, and TLR 10, both showed signs of having been borrowed from Neanderthals and having picked up adaptive mutations at various points in history. Meanwhile, a group led by Janet Kelso of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, used both the same previously published Neanderthal introgression map that Quintana-Murci used and a second introgression map. The researchers searched for borrowed regions of the genome that were especially long and common in present-day humans, eventually zeroing in TLR6, TLR10, and TLR1. These receptors, which detect conserved microbial proteins such as flagellin, are all encoded along the same segment of DNA on chromosome four.

"This modular case study tells the story of Dan and Annie, a married couple of Acadian ancestry who have a genetic form of deafblindness called Usher syndrome. They live in Southwest Louisiana, home of the largest population of DeafBlind citizens in the United States. Acadian Usher syndrome is caused by an allele of the USH1C gene that came to Louisiana with the first Acadian settlers from Canada who founded today's Cajun population. This allele's single nucleotide substitution creates an erroneous splice site that produces a defective cytoskeletal protein (harmonin) of the cochlear and vestibular hair cells and retinal photoreceptors. This splice site is the target of a promising gene therapy. The case study applies and connects Mendelian inheritance, chromosomes, cell division, vision and hearing, DNA sequences, gene expression, gene therapy and population genetics to a specific gene and its movement through generations of Dan and Annie's families.  After the introduction, each of the remaining sections can be used independently either for in-class team activities or out-of-class extensions or assignments over an entire year of introductory undergraduate biology. "

In our first animation of this series we learned how point mutations can edit genetic information. Here we see how duplication events can dramatically lengthen the genetic code of an individual. As point mutations add up in the duplicated region across generations, entirely new genes with new functions can evolve. In the video we see three examples of gene duplications resulting in new traits for the creatures who inherit them: the evolution of a venom gene in snakes, the evolution of leaf digestion genes in monkeys, and the evolution of burrowing legs in hunting dogs.

CRISPR still has a long way to go before it can be used safely and effectively to repair-not just disrupt-genes in people. That is particularly true for most diseases, such as muscular dystrophy and cystic fibrosis, which require correcting genes in a living person because if the cells were first removed and repaired then put back, too few would survive. And the need to treat cells inside the body means gene editing faces many of the same delivery challenges as gene transfer-researchers must devise efficient ways to get a working CRISPR into specific tissues in a person, for example. CRISPR also poses its own safety risks. Most often mentioned is that the Cas9 enzyme that CRISPR uses to cleave DNA at a specific location could also make cuts where it's not intended to, potentially causing cancer.

4:30 video When life emerged on Earth about 4 billion years ago, the earliest microbes had a set of basic genes that succeeded in keeping them alive. In the age of humans and other large organisms, there are a lot more genes to go around. Where did all of those new genes come from? Carl Zimmer examines the mutation and multiplication of genes.

The war against malaria has a new ally: a controversial technology for spreading genes throughout a population of animals. Researchers report today that they have harnessed a so-called gene drive to efficiently endow mosquitoes with genes that should make them immune to the malaria parasite-and unable to spread it. On its own, gene drive won't get rid of malaria, but if successfully applied in the wild the method could help wipe out the disease, at least in some corners of the world. The approach "can bring us to zero [cases]," says Nora Besansky, a geneticist at the University of Notre Dame in South Bend, Indiana, who specializes in malaria-carrying mosquitoes. "The mosquitos do their own work [and] reach places we can't afford to go or get to."

n this interrupted case study, students learn about the influence of early fetal nutritional conditions on the expression of genes related to metabolism and growth. Beginning with the true event of a food and fuel embargo that led to famine in the western Netherlands toward the end of World War II, students learn about the historical background of the Dutch Hunger Winter and its social impact. Using real data from the study conducted by Heijmans and coauthors (2008), students then compare the methylation level of a specific gene between individuals conceived during the famine and their unaffected siblings, and how changes in the expression of this metabolically important gene may impact the risk of developing type 2 diabetes. Supported by other studies on mice and in humans, students conclude that in utero events may impact the health of individuals later in life through epigenetic mechanisms. The case is ideally suited for a molecular or cell biology course, but is also appropriate for an introductory biology course in which students have an understanding of descriptive statistics, interpretation of statistical test results, eukaryotic gene structure, and regulation of gene expression.

Students begin by watching the online video clip and completing a worksheet. After that assignment, instructors can decide which of the two activities (or both!) to use in class. In Activity 1, students identify the locations on chromosomes of genes involved in cancer, using a set of 139 "Cancer Gene Cards" and associated posters. In Activity 2, students explore the genetic basis of cancer by examining cards that list genetic mutations found in the DNA of actual cancer patients. Small-group work spurs discussion about the genes that are mutated in different types of cancers and the cellular processes that the affected genes control. The Activity 1 and 2 Overview document provides short summaries of the two activities along with key concepts and learning objectives, background information, references and rubrics, and answers to students' questions. Both cancer discovery activities are appropriate for first-year high school biology (honors or regular), AP and IB Biology. Activity 2 is also appropriate for an undergraduate freshman biology class.

Horn removal through gene editing is a win-win both for the animal and for the farmer, says Muir, who did not take part in this research. "These findings show that you can take highly desirable genes from animals and move them to other members of their species," he told Popular Science. "One could achieve the same results with natural breeding, but gene editing greatly speeds up the process, reducing the time it takes to accomplish the goal from centuries to years."

hose who would much rather prefer to burn the midnight oil than get up early in the morning can find solace in a new research that suggests they might be genetically predisposed to being nocturnal. It is your genes that allow you to be more productive at night-time instead of the day. Researchers from the University of Leicester in the UK have identified about 80 genes that are closely linked to a preference for either morningness or eveningness. Though these genes were identified in fruit flies and appear unrelated to your own body clock, most of these buggers are found in us mammals as well.

The researchers concluded that genetics - or perhaps other factors, such as environmental influences - play a larger role than practice in certain aspects of musical talent such as recognizing pitch and rhythms. Mosey and her colleagues made another interesting finding: Genes may determine a person's motivation to practice. The majority of participants who reported practicing a lot also shared a high percentage of the same genes. "The association between practice and skill was largely due to the same genes, suggesting that practice will not necessarily make you perfect, but it certainly will enhance your skills," Mosey said.

A new study shows that gene editing using CRISPR/Cas9 technology can work in rhesus monkey embryos. The results, published in the current issue of Human Molecular Genetics, open the door for pursuing gene editing in nonhuman primates as models for new therapies, including pharmacological, gene-, and stem cell-based therapies, says Keith Latham, animal science professor at Michigan State University and lead author of the study.