Their findings, which may lead to new therapies and improved diagnostics for retinal disease, will appear online in advance of publication in the journal Nature Genetics on January 17.
A newly recognized class of disease known as "ciliopathies" has caught the attention of the medical community. Ciliopathies are caused by problems in the structure and/or function of cilia, which are small antenna-like structures protruding from the surface of most cells.
The function of cilia has not been understood, but patients with ciliopathies can suffer from a spectrum of problems including retinal blindness, obesity, renal failure, liver fibrosis and mental impairment. Major breakthroughs in the past few years have linked many forms of these diseases with defects in the structure or signaling capacity of the cilia in cells as diverse as retinal, fat, kidney, liver and nerve cells. Because cilia are so widely present on cells throughout the body, many seemingly unrelated diseases are now known to be related through functions of cilia.
"We are just beginning to uncover the genetic causes for these disorders, but more research is needed to understand why patients with these particular genetic alterations have such variable diseases," said Joseph G. Gleeson, MD, professor of neurosciences and pediatrics at UC San Diego and Howard Hughes Medical Institute Investigator, who supervised the work.
The scientists, led by Gleeson and UCSD graduate student Carrie M. Louie, discovered that loss of the AHI1 gene, which had already been found to cause Joubert Syndrome, a ciliopathy of mental retardation and impaired balance, also caused severe early onset retinal degeneration in the mouse model that they created. This model resembled the most common form of inherited blindness, which is due to degeneration of the retina at an early age.
Further investigation revealed that retinal photoreceptor cells in the mouse model were most likely dying as a result of a toxic accumulation of the very photopigment that receives light signals in the eye and is crucial for normal vision. This finding sheds light on one of the potential causes of retinal degeneration, protein mis-trafficking, which has been of fundamental interest in the study of inherited blindness, according to Gleeson.
The group then tested whether mutations in genes might contribute to retinal blindness in other related diseases. Their analysis of a group of European patients suggests that this is the case. The scientists found that patients carrying a particular genetic alteration were between five and ten times more likely to have retinal blindness, and that some forms of this blindness may be particularly amenable to gene therapy.
"These results may lead to better screening and future therapies for congenital blindness," said Louie. "As routine sequencing of the human genome becomes more and more feasible, studies like ours will help pinpoint which genetic alterations increase the risk of having a certain disease, or the likelihood that your children will have the disease."
Additional contributors to the study include Gianluca Caridi and Gian Marco Ghiggeri of the Giannina Gaslini Institute of Genoa, Italy; Vanda S. Lopes and David S. Williams of the Jules Stein Eye Institute, UCLA; Francesco Brancati and Enza Maria Valente of the CSS-Mendel Institute and G. d'Annunzio University, Italy; Andreas Kispert of the Institute for Molecular Biology, Hannover Medical School, Germany; Madeline Lancaster and Andrew Schlossman of UC San Diego; Edgar A. Otto, John F. O'Toole, and Friedhelm Hildebrandt of the University of Michigan; Michael Leitges of the Biotechnology Centre of Oslo, Norway; Hermann-Josef Groene of the German Cancer Research Center of Heidelberg, Germany; Irma Lopez and Robert K. Koenekoop of the McGill University Health Centre, Canada; Harini V. Gudiseva and Radha Ayyagari of UC San Diego; Elena Vallespin and Carmen Ayuso of the Fundación Jiménez Díaz, Spain, Frans P. Cremers and Anneke I den Hollander of the Radboud University Nijmegen, the Netherlands; and Bruno Dallapiccola of the Bambino Gesù Hospital, Italy.
This study was funded in part by the National Institutes of Health, the Burroughs Wellcome Fund, and the Howard Hughes Medical Institute.
Debra Kain | EurekAlert!
When predictions of theoretical chemists become reality
22.05.2020 | Technische Universität Dresden
From artificial meat to fine-tuning photosynthesis: Food System Innovation – and how to get there
20.05.2020 | Potsdam-Institut für Klimafolgenforschung
Microelectronics as a key technology enables numerous innovations in the field of intelligent medical technology. The Fraunhofer Institute for Biomedical Engineering IBMT coordinates the BMBF cooperative project "I-call" realizing the first electronic system for ultrasound-based, safe and interference-resistant data transmission between implants in the human body.
When microelectronic systems are used for medical applications, they have to meet high requirements in terms of biocompatibility, reliability, energy...
Thomas Heine, Professor of Theoretical Chemistry at TU Dresden, together with his team, first predicted a topological 2D polymer in 2019. Only one year later, an international team led by Italian researchers was able to synthesize these materials and experimentally prove their topological properties. For the renowned journal Nature Materials, this was the occasion to invite Thomas Heine to a News and Views article, which was published this week. Under the title "Making 2D Topological Polymers a reality" Prof. Heine describes how his theory became a reality.
Ultrathin materials are extremely interesting as building blocks for next generation nano electronic devices, as it is much easier to make circuits and other...
Scientists took a leukocyte as the blueprint and developed a microrobot that has the size, shape and moving capabilities of a white blood cell. Simulating a blood vessel in a laboratory setting, they succeeded in magnetically navigating the ball-shaped microroller through this dynamic and dense environment. The drug-delivery vehicle withstood the simulated blood flow, pushing the developments in targeted drug delivery a step further: inside the body, there is no better access route to all tissues and organs than the circulatory system. A robot that could actually travel through this finely woven web would revolutionize the minimally-invasive treatment of illnesses.
A team of scientists from the Max Planck Institute for Intelligent Systems (MPI-IS) in Stuttgart invented a tiny microrobot that resembles a white blood cell...
By studying the chemical elements on Mars today -- including carbon and oxygen -- scientists can work backwards to piece together the history of a planet that once had the conditions necessary to support life.
Weaving this story, element by element, from roughly 140 million miles (225 million kilometers) away is a painstaking process. But scientists aren't the type...
Study co-led by Berkeley Lab reveals how wavelike plasmons could power up a new class of sensing and photochemical technologies at the nanoscale
Wavelike, collective oscillations of electrons known as "plasmons" are very important for determining the optical and electronic properties of metals.
19.05.2020 | Event News
07.04.2020 | Event News
06.04.2020 | Event News
25.05.2020 | Medical Engineering
25.05.2020 | Information Technology
25.05.2020 | Information Technology