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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.

Within every cell in our body, two copies of a tumor suppressor gene called BRCA1 are tasked with regulating the speed at which cells divide. Michael Windelspecht explains how these genes can sometimes mutate, making those cells less specialized and more likely to develop into cancer.

Researchers led by Terra D. Barnes of Washington University discovered that their genetically-engineered mice stutter due to DNA defects in a humdrum "housekeeping" gene. This gene codes for a protein that simply places a "routing tag" on certain enzymes that shred cellular trash. The tag ensures that the shredding enzymes end up in chambers called lysosomes, basically the cell's garbage disposal. It's a mundane cellular activity, yet mutations in the same process in humans have also been linked to stuttering-a bizarrely specific condition for such a general gene. And, so far, scientists have no idea why the two are linked.

Now, scientists at the Salk Institute for Biological Studies in La Jolla, Calif., have pinpointed a gene linked to these disorders that seems to be crucial for normal brain structure in prenatal development. The findings, which appear in an open-access article in the Jan. 14 issue of Cell Reports, shed new light on the mechanistic workings of a gene called MDGA1, previously implicated in autism, schizophrenia and bipolar disorder.

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.

Huntington disease is caused by a mutation in the HTT gene. Understanding how the mutation causes neurodegeneration might help researchers develop treatments that protect brain function. This animation describes the genetic defect that underlies Huntington disease. Created by the editors at Nature Reviews Disease Primers.

Scientists are now one step closer to understanding how genetic mutations contribute to autism. In a study released Thursday in the journal Cell, experts from UNC School of Medicine discovered how one specific autism-linked gene mutation actually works

Explore eight different mutations with graphics, gene explanations, and phenotypic effects.

Malaria has long been a problem in Mali. But in 2006, the situation got worse: a malaria-carrying mosquito species named Anopheles coluzzii became increasingly resistant to common insecticides. Scientists searched for an explanation in its genes. Somehow, the species had acquired mutations that were previously only found in another species, Anopheles gambiae - despite the fact that these two species didn't usually mate with each other, and that their hybrids tended to die without producing offspring of their own, the mutations were identical.

Technical details aside, Crispr-Cas9 makes it easy, cheap, and fast to move genes around-any genes, in any living thing, from bacteria to people. "These are monumental moments in the history of biomedical research," Baltimore says. "They don't happen every day." Using the three-year-old technique, researchers have already reversed mutations that cause blindness, stopped cancer cells from multiplying, and made cells impervious to the virus that causes AIDS. Agronomists have rendered wheat invulnerable to killer fungi like powdery mildew, hinting at engineered staple crops that can feed a population of 9 billion on an ever-warmer planet. Bioengineers have used Crispr to alter the DNA of yeast so that it consumes plant matter and excretes ethanol, promising an end to reliance on petrochemicals. Startups devoted to Crispr have launched. International pharmaceutical and agricultural companies have spun up Crispr R&D. Two of the most powerful universities in the US are engaged in a vicious war over the basic patent.

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.

This video excerpt from NOVA uncovers the genetic mystery that nearly killed Alexis, now 14, and introduces the debate surrounding genetic testing at birth. After diagnosing Alexis and her twin brother Noah with cerebral palsy at a young age, doctors later discovered that the twins shared a rare genetic mutation that led to a condition that mimics cerebral palsy. The twins improved after receiving treatment, but then Alexis took a turn for the worse. Thanks to whole genome sequencing, doctors discovered a second problem linked to the mutation and gave her a different treatment that saved her life.

This clicker case was designed to teach students about basic enzyme structure, mechanisms of enzyme inhibition, and mechanisms of drug resistance. The story follows Oliver Casey, a patient afflicted with Chronic Myelogenous Leukemia (CML). CML is caused by a chromosomal mutation that affects the tyrosine kinase ABL, an enzyme important in regulating cell growth and proliferation. The chromosomal mutation gives rise to the BCR-ABL fusion gene that produces a constitutively active ABL kinase, which causes the leukemia. In May 2001, the Food and Drug Administration approved the use of a rationally designed tyrosine kinase inhibitor, imatinib (Gleevec®), for the treatment of CML. During that same month, Gleevec made the cover of TIME magazine, described as "new ammunition in the war on cancer." The case is structured for a flipped classroom environment in which students view preparatory videos (including one by the author) on their own before beginning the case. Written for a first-year introductory biology course, the case could also be adapted for AP/Honors high school biology or a cancer biology course.

This "clicker case" tells the story of "Hannah," a baby girl adopted by two loving parents who grows up with an uncontrolled appetite and develops severe early-onset obesity. Students follow Hannah's story as she develops excessive eating early in life, which her health care team is unable to explain. A visit to obesity specialists finally reveals the underlying cause of Hannah's obsession with food: extremely low levels of circulating leptin, a hormone that regulates appetite and body weight. It is further discovered that Hannah's leptin deficiency is due to a mutation in the LEP gene. As the story unfolds, students first work on unit conversions and BMI calculations to practice quantitative skills as well as graph and data interpretation skills. Students then apply their knowledge of DNA transcription, translation, and protein structure to answer questions based on figures from a 2019 study on LEP mutations. The case is best suited for high school and lower-level undergraduate biology courses.

Over the last decade, as DNA-sequencing technology has grown ever faster and cheaper, our understanding of the human genome has increased accordingly. Yet scientists have until recently remained largely ham-fisted when they've tried to directly modify genes in a living cell. Take sickle-cell anemia, for example. A debilitating and often deadly disease, it is caused by a mutation in just one of a patient's three billion DNA base pairs. Even though this genetic error is simple and well studied, researchers are helpless to correct it and halt its devastating effects.

Find out how researchers identify genetic diseases and determine possible treatments. short film, genes as medicine click and learn, central dogma scientists at work, the search for a mutated gene central dogma card activity animation, CF mechanism and treatment click and learn. CRISPR-Cas9

Humans may in part owe their big brains to a DNA "typo" in their genetic code, research suggests. The mutation was also present in our evolutionary "cousins" - the Neanderthals and Denisovans. However, it is not found in humans' closest living relatives, the chimpanzees. As early humans evolved, they developed larger and more complex brains, which can process and store a lot of information. Last year, scientists pinpointed a human gene that they think was behind the expansion of a key brain region known as the neocortex.

A soft brush that feels like prickly thorns. A vibrating tuning fork that produces no vibration. Not being able to tell which direction body joints are moving without looking at them. Those are some of the bizarre sensations reported by a 9-year-old girl and 19-year-old woman in a new study. The duo, researchers say, shares an extremely rare genetic mutation that may shed light on a so-called "sixth sense" in humans: proprioception, or the body's awareness of where it is in space. The new work may even explain why some of us are klutzier than others.

Scientists at the University of California, San Diego School of Medicine have found that mutations that cause autism in children are connected to a pathway that regulates brain development.

Residents of the Solomon Islands in the Pacific have some of the darkest skin seen outside of Africa. They also have the highest occurrence of blond hair seen in any population outside of Europe. Now, researchers have found the single gene that explains these fair tresses.