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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.

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.

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.

In the August 1 issue of CELL, researchers from the Gene and Stem Cell Therapy Program at Sydney's Centenary Institute revealed another function of introns, or noncoding nucleotide sequences, in DNA. They reported that gene-sequencing techniques and computer analysis allowed them to demonstrate how granulocytes use noncoding DNA to regulate the activity of a group of genes that determines the cells' shape and function.

Because the gene-enzyme system forms a closed loop, it presents us with a classic chicken or egg conundrum: Which came first, genes or the protein enzymes they code for? While the details are still not fully worked out, discoveries over the past few decades have lead researchers to a surprising possible solution: What really came first? Genes that act as enzymes! The RNA World Hypothesis is the idea that before living cells, the genetic code, and the gene/protein cycle ever existed, chains of a chemical called RNA were forming naturally. Once formed, some of these chains were able to function as enzymes, and were even able to evolve by making copies of themselves with slight, accidental modifications.

The researchers isolated different subpopulations of human brain stem cells and precisely identified, which genes are active in which cell type. In doing so, they noticed the gene ARHGAP11B: it is only found in humans and in our closest relatives, the Neanderthals and Denisova-Humans, but not in chimpanzees. This gene manages to trigger brain stem cells to form a bigger pool of stem cells. In that way, during brain development more neurons can arise and the cerebrum can expand. The cerebrum is responsible for cognitive functions like speaking and thinking.

Why does a snake have 25 or more rows of ribs, whereas a mouse has only 13? The answer, according to a new study, may lie in "junk DNA," large chunks of an animal's genome that were once thought to be useless. The findings could help explain how dramatic changes in body shape have occurred over evolutionary history. Scientists began discovering junk DNA sequences in the 1960s. These stretches of the genome-also known as noncoding DNA-contain the same genetic alphabet found in genes, but they don't code for the proteins that make us who we are. As a result, many researchers long believed this mysterious genetic material was simply DNA debris accumulated over the course of evolution. But over the past couple decades, geneticists have discovered that this so-called junk is anything but. It has important functions, such as switching genes on and off and setting the timing for changes in gene activity. 

The activity of some of our genes varies with the seasons throughout the year. The discovery comes from an analysis of blood samples from more than 16,000 people in both hemispheres. The most striking pattern was that 147 genes involved in the immune system made it more reactive or "pro-inflammatory" during winter or rainy seasons, probably to battle the onslaught of cold and flu viruses

Explore gene regulation with the Amoeba Sisters, including the fascinating Lac Operon found in bacteria! Learn how genes can be turned "on" and "off" and why this is essential for cellular function.

In this case, developed for an introductory genetics class, students meet a woman whose family has a history of colon cancer. Students create a pedigree based on information from the case and discuss what it means to be genetically predisposed to cancer. Using bioinformatics tools from the NCBI database, students identify and examine the mutation in the woman's APC gene that results in genetic predisposition to colon cancer. Finally, they investigate the biological function of the APC protein to understand why this mutation contributes to the development of cancer and determine whether APC is a proto-oncogene, tumor suppressor gene, or genome stability gene.

Panobinostat is a new type of drug that works by blocking an enzyme responsible for modifying DNA at the epigenetic level. Epigenetics refers to chemical marks on DNA itself or on the protein "spools" called histones that package DNA. These marks influence the activity of genes without changing the underlying sequence, essentially acting as volume knobs for genes. Earlier genomic studies showed that about 80 percent of DIPG tumors carry a mutation that alters a histone protein, resulting in changes to the way DNA is packaged and tagged with those chemical marks. This faulty epigenetic regulation results in activation of growth-promoting genes that should have been turned off, and shutdown of others that should have acted as brakes to cell multiplication. Cancer is the result. Panobinostat appears to work by restoring proper functioning of the cells' chemical tagging system.

The mystery of where these orphan genes came from has puzzled scientists for decades. But in the past few years, a once-heretical explanation has quickly gained momentum - that many of these orphans arose out of so-called junk DNA, or non-coding DNA, the mysterious stretches of DNA between genes. "Genetic function somehow springs into existence," said David Begun, a biologist at the University of California, Davis.

Like humans, some golden retrievers develop Duchenne muscular dystrophy (DMD), a hereditary muscle wasting condition that begins early in life. Using gene therapy, scientists were able to restore muscle function in dogs with the disease, according to a study published today (July 25) in Nature Communications.

Current CRISPR-based screens often mutate the beginning of a gene, which sometimes results in the expression of a functional protein variant. To circumvent this problem, researchers at Cold Spring Harbor Laboratory (CSHL) designed CRISPR guide RNAs that would mutate the portion of a gene encoding a domain on the surface of the protein where a small molecule could bind to alter the protein's function. The team had previously identified such a binding pocket on the protein BRD4, and a small molecule inhibitor that binds in the pocket is an effective leukemia treatment.

de Villena and his colleagues counted the RNA molecules produced and found that genes from the father produced on average more RNA than genes from the mother. (And remember, RNA directs the production of proteins, which are the workhorses of the body's development and function.) The implication? "It's not only what you inherit, but from whom you inherit," he said.

One of the most important molecules relating to cancer is called p53. This Click and Learn explains the structure and function of the p53 protein as well as how the protein's activity is regulated. Learn why p53 is called the guardian of the genome and how interfering with its function can lead to cancer.

This directed case study examines the molecular basis of cystic fibrosis to emphasize the relationship between the genetic code stored in a DNA sequence and the encoded protein's structure and function. Cystic fibrosis is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) protein that functions to help maintain salt and water balance along the surface of the lung and gastrointestinal tract. This case introduces students to "Maggie," who has just been diagnosed with cystic fibrosis. The students must identify the mutation causing Maggie's disease by transcribing and translating a portion of the wildtype and mutated CFTR gene. Students then compare the three-dimensional structures of the resulting proteins to better understand the effect a single amino acid mutation can have on the overall shape of a protein. Students also review the concepts of tonicity and osmosis to examine how the defective CFTR protein leads to an increase in the viscosity of mucus in cystic fibrosis patients. This case was developed for use in an introductory college-level biology course but could also be adapted for use in an upper-level cell or molecular biology course.

Stress isn't always a bad thing; it can be handy for a burst of extra energy and focus, like when you're playing a competitive sport or have to speak in public. But when it's continuous, it actually begins to change your brain. Madhumita Murgia shows how chronic stress can affect brain size, its structure, and how it functions, right down to the level of your genes.

Last month, researchers announced they were studying a 30,000-year-old giant virus called Mollivirus sibericum that they found in melted Siberian permafrost. The virus was functional and able to infect amoeba. This isn't the first time researchers have found big viruses that have challenged what we thought we knew about the tiny invaders. Mimivirus, discovered in 2003, has 1,200 genes and is twice the width of traditional viruses.