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In the study, published Monday (May 1) in Nature Biotechnology,  Luo and colleagues set their sights on two fusions genes they had previously found to be associated with prostate cancer and various forms of rapid and invasive cancer, including liver tumors. Using a modified CRISPR-Cas9 tool that creates a single- rather than double-stranded break in DNA, they targeted the chromosomal breakpoints that form these fusion genes and replaced fusion DNA with a gene encoding the enzyme HSV1-tk. This enzyme effectively kills tumor cells by converting the drug ganciclovir into its active form, which then blocks DNA synthesis and leads to cell death. (Ganciclovir is used to treat cytomegalovirus in humans.)

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.

When Jordan is diagnosed with brain cancer (glioblastoma multiform), his college plans are unexpectedly put on hold. This scenario is presented in order to teach students about gene regulation, as the efficacy of the drug Jordan receives for post-surgical treatment is dependent upon the activity level of a gene encoding a protein involved in DNA repair. This "flipped" case study requires students to prepare in advance outside of class by watching several short videos that have been selected to teach the basics of how cancer forms as well as the role of epigenetics in gene silencing. Inside of class, the case is delivered using progressive disclosure format in which students gradually receive additional information to answer a series of directed questions. To determine a treatment plan for Jordan, students analyze data from a research study involving patients treated for his specific type of cancer. The case is designed for advanced high school biology classes as well as lower-level undergraduate general biology courses for non-majors and majors.

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 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

Fascinating narrative science that explores the next frontier in medicine and genetics through the very personal prism of the children and families gene therapy has touched. Eight-year-old Corey Haas was nearly blind from a hereditary disorder when his sight was restored through a delicate procedure that made medical history.  Like something from a science fiction novel, doctors carefully introduced viruses bearing healing genes into Corey's eyes-a few days later, Corey could see, his sight restored by gene therapy.

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.

Using a pre-drawn template can be helpful during a consultation to explain single gene inheritance. Our template shows one pair of chromosomes for each parent. Each chromosome has a single gene highlighted that can be coloured in to illustrate a gene alteration. You can then show which sperm and/or eggs contain the chromosome with the gene alteration and the different genetic combinations that could be present at conception.

In this activity, we will work with the two groups of genes that control the cell cycle, proto-oncogenes and tumor suppressor genes. We will also add a new group of genes that are in charge of the maintenance of our DNA, the DNA repair system.

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. 

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.

Before the gene treatment, the animals experienced about five serious bleeding events a year. After receiving the novel gene therapy, though, they experienced substantially fewer bleeding events over three years, as reported in the journal Nature Communications.

Chinese scientists say they've genetically modified human embryos for the very first time. The team attempted to modify the gene responsible for beta-thalassaemia, a potentially fatal blood disorder, using a gene-editing technique known as CRISPR/Cas9. Gene editing is a recently developed type of genetic engineering in which DNA is inserted, replaced, or removed. Here, experts weigh-in with ethical questions and considerations.

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.

Tweaking the human genome with current and future gene-editing tools could lead to sophisticated treatments and prevention strategies for disease. The promise of those applications is reason enough to move forward with such work in the lab and clinic, albeit cautiously, the dozen scientists and bioethicists who organized the International Summit on Human Gene Editing said today after three days of deliberation and presentations in Washington, D.C.

More than 400 scientists, bioethicists, and historians from 20 countries on 6 continents have gathered this week in Washington, DC, for the Human Gene Editing Summit. The attendees are a veritable who's who of genome editing: Jennifer Doudna of the University of California, Berkeley, Emmanuelle Charpentier of Max Planck Institute for Infection Biology, and Feng Zhang of the Broad Institute of MIT and Harvard-the three discoverers of the CRISPR-Cas9 system's utility in gene editing-plus dozens of other big names in genome science. Cal Tech's David Baltimore along with the heads of the four national societies hosting the meeting (US National Academy of Sciences, US National Academy of Medicine, Chinese Academy of Sciences, and the U.K.'s Royal Society) provided opening remarks on Tuesday (December 1). And as I sat stage right in the NAS auditorium, I noticed the unmistakable rear profile of Harvard Medical School's George Church three rows in front of me. Church was scheduled to speak at a session later that afternoon about the application of CRISPR and other new precision gene editing techniques to the human germline-a hot-button topic since April, when a Chinese group published it had successfully modified the genomes of human embryos, and the National Institutes of Health (NIH) said it would not fund such research. Then in September, the U.S./U.K.-based Hinxton Group, an international consortium of scientists, policy experts, and bioethicists, said it supported the use of genetic editing in human embryos for limited applications in research and medicine.  

A gene mutation is a permanent alteration in the DNA sequence that makes up a gene, such that the sequence differs from what is found in most people. Mutations range in size; they can affect anywhere from a single DNA building block (base pair) to a large segment of a chromosome that includes multiple genes.

A genetic "crystal ball" can predict whether certain people will respond effectively to the flu vaccine. Nine genes are associated with a strong immune response to the flu vaccine in those aged 35 and under, a new study finds. If these genes were highly active before vaccination, an individual would generate a high level of antibodies after vaccination, no matter the flu strain in the vaccine, researchers report online August 25 in Science Immunology. This response can help a person avoid getting the flu.

This clicker case study follows a dialogue between two college students, Lucy and Dan, as they discover how alternative splicing of mRNA molecules can allow a single gene to code for multiple proteins. Dan is participating in a clinical trial for a drug that may treat his migraines by inhibiting calcitonin gene-related peptide, and Lucy is working in a summer research lab that studies the protein calcitonin. They soon realize that the two proteins are both encoded by the same gene, and through their questioning and dialogue they come to understand the phenomenon of alternative splicing. They also learn about other steps of mRNA processing and about monoclonal antibodies. This case was designed to be taught in a flipped classroom, but could easily be adapted for a more traditional classroom setting if content covered in the pre-class videos is covered during the case study instead. It was designed for an introductory-level molecular biology course, but could be adapted for higher levels by including more information about the physiology and regulatory mechanisms involved.

In the largest study of its kind, a research team has meshed extensive genome data on more than 50,000 people with their electronic health records and identified potential new disease-causing genes. The data further suggest that about one in 250 people may harbor a gene variant that puts them at risk for heart attacks and strokes, yet aren't receiving adequate treatment.