Syndicate content

Archive - Feb 25, 2017

Detailed Searchable Index of Proteins in Genome of Bottlenose Dolphin Developed

In movies and TV shows, dolphins are often portrayed as heroes who save humans through remarkable feats of strength and tenacity. Now, according to a February 23, 2017 press release from the National Institute of Standards and Technology (NIST), dolphins could save the day for humans in real life, too - with the help of emerging technology that can measure thousands of proteins and an improved database full of genetic data. "Dolphins and humans are very, very similar creatures," said the NIST's Dr. Ben Neely, a member of the Marine Biochemical Sciences Group and the lead on a new project at the Hollings Marine Laboratory, a research facility in Charleston, South Carolina that includes the NIST as one of its partner institutions. "As mammals, we share a number of proteins and our bodies function in many similar ways, even though we are terrestrial and dolphins live in the water all their lives." Dr. Neely and his colleagues have just finished creating a detailed, searchable index of all the proteins found in the bottlenose dolphin genome. Dr. Neely's project is built on years of marine mammal research and aims to provide a new level of bioanalytical measurements. The results of this work will aid wildlife biologists, veterinary professionals, and biomedical researchers. Although a detailed map of the bottlenose dolphin (Tursiops truncatus) genome was first compiled in 2008, recent technological breakthroughs have enabled the creation of a new, more exhaustive map of all of the proteins produced by the dolphins' DNA. Dr. Neely led the process to generate the new genome with the help of colleagues at the Hollings Marine Laboratory. For this project, the initial genomic sequencing and assembly were completed by Dovetail Genomics, a private U.S.-based company.

Scientists Document Second Case of Trisomy 22 in Chimps ("Chimpanzee Down Syndrome")

Japanese researchers have confirmed the second case known to science of a chimpanzee born with trisomy 22, a chromosomal defect similar to that of Down syndrome (or trisomy 21) in humans. The report on Kanako (photo), a 24-year-old female chimp born into captivity, was led by Dr. Satoshi Hirata of Kyoto University in Japan, and appeared online on February 21, 2017 in the journal Primates, published by Springer. The article is titled “Chimpanzee Down Syndrome: A Case Study of Trisomy 22 in a Captive Chimpanzee.” The authors also describe their attempts to improve the quality of life of this chimpanzee, through providing and managing opportunities for normal social interaction. Such efforts are seen as key in caring for disabled chimpanzees in captivity. Human cells normally contain 23 pairs of chromosomes, for a total of 46. Down syndrome occurs when a person’s cells contain a third copy of chromosome 21 (also known as trisomy 21). In turn, apes have 24 pairs of chromosomes, for a total of 48. Trisomy 22 is diagnosed when the cells of apes such as chimpanzees, gorillas, or orangutans contain a third copy of chromosome 22. The first confirmed case of a chimpanzee with trisomy 22 was documented in 1969. The chimpanzee described nearly five decades ago died before its second birthday. This means that Kanako is the longest-living chimp with this chromosomal disorder that scientists are aware of. Kanako was born in captivity in 1992, at a facility which was transferred to Kyoto University in 2011 and renamed as Kumamoto Sanctuary, Wildlife Research Centre. She experienced stunted growth from an early age, suffers from a congenital heart disease and has underdeveloped teeth. Kanako developed cataracts before the age of one, and became blind by the age of seven.

Four Variants of GLRB Gene ID’d As Risk Factors for Anxiety Disorders

Mental, social, and inherited factors all play a role in anxiety disorders. In an article published online on February 7, 2017 in Molecular Psychiatry, a research team from Julius-Maximilians-Universität Würzburg (JMU) in Bavaria, Germany, describes a hitherto unknown genetic pathway for developing such diseases: The scientists pinpointed at least four variants of the GLRB gene (glycine receptor B) as risk factors for anxiety and panic disorders. More than 5,000 voluntary participants and 500 patients afflicted by panic disorder took part in the study that delivered these results. In Germany, approximately 15 percent of adults suffer from anxiety and panic disorders. Some people may have an extreme fear of spiders or other objects while others have breathing difficulties and accelerated heart beat in small rooms or large gatherings of people. With some afflicted persons, the anxiety attacks occur for no apparent cause. Many patients suffer from the detrimental impacts on their everyday lives - they often have problems at work and withdraw from social contacts. The Molecular Psychiatry article is titled “GLRB Allelic Variation Associated with Agoraphobic Cognitions, Increased Startle Response and Fear Network Activation: A Potential Neurogenetic Pathway to Panic Disorder.” How are fear and anxiety triggered? How do anxiety disorders arise and evolve? Scientists from Münster, Hamburg, and Würzburg have looked into these questions within the scope of Collaborative Research Center (CRC) TR 58 funded by Deutsche Forschungsgemeinschaft. Their goal is to develop new therapies that are better tailored to the individual patients. Anxiety disorders can be treated with drugs and behavior therapy for instance.

New Approach Permits Revelation of Diverse Allelic Effects in Mammalian Brain That Are Not Caused by Imprinting or Genetic Variation

For over a century, scientists have thought that most of our cells express genes from both parents' chromosomes relatively equally throughout life. But the biology is more nuanced, say scientists who invented a screen to measure the activity of specific genes from both parents. In Neuron on February 23, 2017, researchers report that in rodent, monkey, and human brains, it's not unusual for individual neurons or specific types of neurons to silence genes from one parent or the other. The article is titled “Diverse Non-genetic, Allele-Specific Expression Effects Shape Genetic Architecture at the Cellular Level in the Mammalian Brain.” Surprisingly, the differential activation of maternal and paternal gene copies was observed most often in the developing brain, impacting about 85% of genes. Gradually, as the brain matures, neurons increasingly express both parents' genes equally. However, for at least 10% of genes, maternal and paternal copies continue to be differentially expressed in the adult brain, revealing that this imbalance exists throughout an organism's lifetime for many genes in the brain. "This story has its roots in understanding why we reproduce sexually--normally, having two copies of a gene acts as a protect buffer in case one is defective," says senior author Dr. Christopher Gregg, a neurobiologist at the University of Utah School of Medicine and a New York Stem Cell Foundation Robertson Investigator. "Our findings suggest that periods when the healthy gene copy is turned off could be critical windows during which cells are particularly vulnerable to a mutation in the other copy."