Homozygosity mapping reveals new nonsense mutation in the FAM161A gene causing autosomal recessive retinitis pigmentosa in a Palestinian family

Purpose: Retinitis pigmentosa (RP) is a heterogenous group of inherited retinal degenerations caused by mutations in at least 45 genes. Recently, the FAM161A gene was identified as the causative gene for RP28, an autosomal recessive form of RP. Methods: We performed a clinical and molecular genetic study of a consanguineous Palestinian family with two three siblings affected with retinitis pigmentosa. DNA samples were collected from the index patient, his father, his affected sister, and two non-affected brothers. DNA sample from the index was subjected to high resolution genome-wide SNP array. Assuming identity-by-descent in this consanguineous family we applied homozygosity mapping to identify disease causing genes. Results: The index patient reported night blindness since the age of 20 years, followed by moderate disease progression with decrease of peripheral vision, the development of photophobia and later on reduced central vision. At the age of 40 his visual acuity was counting fingers (CF) for both eyes, color discrimination was not possible and his visual fields were severely constricted. Funduscopic examination revealed a typical appearance of advanced RP with optic disc pallor, narrowed retinal vessels, bone-spicule like pigmentary changes in the mid-periphery and atrophic changes in the macula. His younger affected brother (37 years) was reported with overall milder symptoms, while the youngest sister (21 years) reported problems only with night vision. Applying high-density SNP arrays we identified several homozygous genomic regions one of which included the recently identified FAM161A gene mutated in RP28-linked autosomal recessive RP. Sequencing analysis revealed the presence of a novel homozygous nonsense mutation, c.1003C>T/p.R335X in the index patient and the affected sister. Conclusion: We identified an RP28-linked RP family in the Palestinian population caused by a novel nonsense mutation in FAM161A. RP in this family shows a typical disease onset with moderate to rapid progression into severe visual impairment including central vision in the index and overall milder symptoms in the younger brother and sister.We thank the family members for participation in this study. We also thank the Microarray Facility at the Medical Faculty of the Tübingen University for SNP chip processing. This work was supported by a Trilateral German-Israel-Palestinian Authority program grant of the Deutsche Forschungsgemeinschaft (SCHO 754/5–1 and WI1189/8–1)

De novo intrachromosomal gene conversion from OPN1MW to OPN1LW in the male germline results in Blue Cone Monochromacy

X-linked cone dysfunction disorders such as Blue Cone Monochromacy and X-linked Cone Dystrophy are characterized by complete loss (of) or reduced L- and M- cone function due to defects in the OPN1LW/OPN1MW gene cluster. Here we investigated 24 affected males from 16 families with either a structurally intact gene cluster or at least one intact single (hybrid) gene but harbouring rare combinations of common SNPs in exon 3 in single or multiple OPN1LW and OPN1MW gene copies. We assessed twelve different OPN1LW/MW exon 3 haplotypes by semi-quantitative minigene splicing assay. Nine haplotypes resulted in aberrant splicing of ≥20% of transcripts including the known pathogenic haplotypes (i.e. ‘LIAVA’, ‘LVAVA’) with absent or minute amounts of correctly spliced transcripts, respectively. De novo formation of the ‘LIAVA’ haplotype derived from an ancestral less deleterious ‘LIAVS’ haplotype was observed in one family with strikingly different phenotypes among affected family members. We could establish intrachromosomal gene conversion in the male germline as underlying mechanism. Gene conversion in the OPN1LW/OPN1MW genes has been postulated, however, we are first to demonstrate a de novo gene conversion within the lineage of a pedigree

GLRB allelic variation associated with agoraphobic cognitions, increased startle response and fear network activation : a potential neurogenetic pathway to panic disorder

The molecular genetics of panic disorder (PD) with and without agoraphobia (AG) are still largely unknown and progress is hampered by small sample sizes. We therefore performed a genome-wide association study with a dimensional, PD/AG - related anxiety phenotype based on the Agoraphobia Cognition Questionnaire (ACQ) in a sample of 1,370 healthy German volunteers of the CRC TRR58 MEGA study wave 1. A genome-wide significant association was found between ACQ and single non-coding nucleotide variants of the GLRB gene (rs78726293, p=3.3x10-8; rs191260602, p=3.9x10-8). We followed up on this finding in a larger dimensional ACQ sample (N=2,547) and in independent samples with a dichotomous AG phenotype based on the Symptoms Checklist (SCL-90; N=3,845) and a case control sample with the categorical phenotype PD/AG (Ncombined =1,012) obtaining highly significant p-values also for GLRB single nucleotide variants rs17035816 (p=3.8x10-4) and rs7688285 (p=7.6x10-5). GLRB gene expression was found to be modulated by rs7688285 in brain tissue as well as cell culture. Analyses of intermediate PD/AG phenotypes demonstrated increased startle reflex and increased fear network as well as general sensory activation by GLRB risk gene variants rs78726293, rs191260602, rs17035816 and rs7688285. Partial Glrb knockout-mice demonstrated an agoraphobic phenotype. In conjunction withthe clinical observation that rare coding GLRB gene mutations are associated with the neurological disorder hyperekplexia characterized by a generalized startle reaction and agoraphobic behavior, our data provide evidence that non-coding, though functional GLRB gene polymorphisms may predispose to PD by increasing startle response and agoraphobic cognitions.PostprintPeer reviewe

Multiexon deletion alleles of ATF6 linked to achromatopsia

Achromatopsia (ACHM) is an autosomal recessive disease that results in severe visual loss. Symptoms of ACHM include impaired visual acuity, nystagmus, and photoaversion starting from infancy; furthermore, ACHM is associated with bilateral foveal hypoplasia and absent or severely reduced cone photoreceptor function on electroretinography. Here, we performed genetic sequencing in 3 patients from 2 families with ACHM, identifying and functionally characterizing 2 mutations in the activating transcription factor 6 (ATF6) gene. We identified a homozygous deletion covering exons 8-14 of the ATF6 gene from 2 siblings from the same family. In another patient from a different family, we identified a heterozygous deletion covering exons 2 and 3 of the ATF6 gene found in trans with a previously identified ATF6 c.970C>T (p.Arg324Cys) ACHM disease allele. Recombinant ATF6 proteins bearing these exon deletions showed markedly impaired transcriptional activity by qPCR and RNA-Seq analysis compared with WT-ATF6. Finally, RNAscope revealed that ATF6 and the related ATF6B transcripts were expressed in cones as well as in all retinal layers in normal human retina. Overall, our data identify loss-of-function ATF6 disease alleles that cause human foveal disease

Temporal and spatial analysis of the 2014-2015 Ebola virus outbreak in West Africa

West Africa is currently witnessing the most extensive Ebola virus (EBOV) outbreak so far recorded. Until now, there have been 27,013 reported cases and 11,134 deaths. The origin of the virus is thought to have been a zoonotic transmission from a bat to a two-year-old boy in December 2013 (ref. 2). From this index case the virus was spread by human-to-human contact throughout Guinea, Sierra Leone and Liberia. However, the origin of the particular virus in each country and time of transmission is not known and currently relies on epidemiological analysis, which may be unreliable owing to the difficulties of obtaining patient information. Here we trace the genetic evolution of EBOV in the current outbreak that has resulted in multiple lineages. Deep sequencing of 179 patient samples processed by the European Mobile Laboratory, the first diagnostics unit to be deployed to the epicentre of the outbreak in Guinea, reveals an epidemiological and evolutionary history of the epidemic from March 2014 to January 2015. Analysis of EBOV genome evolution has also benefited from a similar sequencing effort of patient samples from Sierra Leone. Our results confirm that the EBOV from Guinea moved into Sierra Leone, most likely in April or early May. The viruses of the Guinea/Sierra Leone lineage mixed around June/July 2014. Viral sequences covering August, September and October 2014 indicate that this lineage evolved independently within Guinea. These data can be used in conjunction with epidemiological information to test retrospectively the effectiveness of control measures, and provides an unprecedented window into the evolution of an ongoing viral haemorrhagic fever outbreak.status: publishe

Abstracts from the 20th International Symposium on Signal Transduction at the Blood-Brain Barriers

https://deepblue.lib.umich.edu/bitstream/2027.42/138963/1/12987_2017_Article_71.pd

Current practice of diagnostics and therapy of pelvic floor disorders in gynocological surgeries in Germany

Genitaldeszensus und Inkontinenz gehören zu den häufigen Beschwerdebildern in der Gynäkologie. Sie können unabhängig voneinander, aber auch vergesellschaftet auftreten und können mit einem erheblichen Leidensdruck der Patientinnen einhergehen. In der vorliegenden Arbeit wurde untersucht, in wieweit die derzeit existenten Strukturen im Gesundheitswesen der Bewältigung neuer Aufgaben im Management der großen Erkrankungszahlen gerecht werden können. Ein Fragebogen wurde für diese Arbeit erstellt und an gynäkologische Praxen in Berlin versand. Mit einer Untersuchung der Ist-Situation sollten objektive und subjektive Grenzen bei Diagnostik und Therapie unter Berücksichtigung der gerätetechnischen Ausstattung und Subspezialisierung betrachtet werden. Es erfolgte eine Analyse der Realität in den Praxen gemessen am derzeitigen Stand der verfügbaren und in Leitlinien und Empfehlungen internationaler Organisationen beschriebenen validen diagnostischen und therapeutischen Möglichkeiten im Management der Beckenbodenerkrankungen. 248 Praxen wurden auf postalischem Weg angeschrieben und schriftlich um die Teilnahme an der Umfrage gebeten. Jeweilige Unterschiede in der Beantwortung der Fragen wurden mittels Chi-Quadrat Test auf Signifikanz überprüft. Eine Signifikanz wurde ab einem P-Wert unter 0,05 angenommen. Ergebnisse: Eine Rücklaufquote von 31% wurde erreicht. 70 ausgefüllte Fragebögen konnten für die statistische Auswertung verwendet werden. Im Durchschnitt wird von den Ärzten eine Patientinnenzahl mit Beckenbodenerkrankungen pro Quartal von 59 angegeben. Der Median liegt bei 30 Patientinnen. Die absoluten Zahlen variieren dabei sehr deutlich zwischen 5 und 350. 97% der befragten Ärzte geben an, ihre Patientinnen immer auf das Vorhandensein einer Harninkontinenz anzusprechen. In 40% der Praxen nutzen die Ärzte in der klinischen Routineuntersuchung den Stresstest zur Beurteilung der Harninkontinenz. Im Rahmen ihrer Basisdiagnostik legen 33% aller Praxen Wert auf den Ausschluss eines pathologischen Restharns. 53% der befragten Praxen führen diese Diagnostik nur sporadisch und nicht zwingend durch und 14% halten diese Maßnahme bei Ihrer Diagnostik für nicht erforderlich. Die Perineal- bzw. Introitussonographie wird inzwischen in 37% der befragten Praxen in ein festes Abklärungskonzept einbezogen. Alle Ärzte, die unter einem Jahr in ihrer gynäkologischen Praxis tätig sind, nutzen häufig oder fast immer die Introitus- bzw. Perinealsonographie in der Diagnostik von Beckenbodenerkrankungen und/ oder Harninkontinenz. Signifikant ist, dass alle Ärzte, die nie eine Introitus- bzw. Perinealsonographie durchführen, länger als 10 Jahre niedergelassen sind. In 60 Praxen setzen die Ärzte nach anamnestisch und klinisch gesicherter Beckenbodenerkrankung die Diagnostik in der eigenen Praxis weiter fort. Beim Einsatz von Prodry-Kontinenz-Tampons ist ein signifikanter Unterschied zwischen Einzel- und Gemeinschaftspraxen ersichtlich. Bei Einweisung zur OP wird nach durchgeführter Basisdiagnostik von 64 Praxen eine Verdachtsdiagnose formuliert und die spezialisierte Diagnostik sowie die Entscheidung über das OP-Verfahren ausschließlich der Klinik überlassen. Die Mehrheit der Praxen (84%) ist gegenüber einer ambulanten Vorsprechstunde in der operierenden Einrichtung positiv eingestellt. Fazit: Die zumeist ausführlichen Antworten der Kollegen weisen auf ein generelles Interesse und auf die Akzeptanz hin, dieser Patientengruppe einen ihrer Prävalenz und der Notwendigkeit eines aktiven Angehens entsprechenden Stellenwert einzuräumen. Ein Paradigmenwechsel bei den niedergelassenen Kollegen beim Umgang mit solchen großen Indikationsgruppen ist zu spüren, da die Mehrheit der Kollegen versucht, sowohl Diagnostik und Therapie umfassend abzudecken – dabei aber auch die interdisziplinäre Zusammenarbeit, ebenso wie die mit dem stationären Bereich (wieder-) zu beleben. Dieser Trend ist vorrangig bei den Kollegen im jüngeren Niederlassungsalter offenkundig. Wie aus den Antworten hervorging, kommt die Erfüllung des Anspruchs, jede Patientin an der entsprechenden Stelle mit den individuellen Bedürfnissen und Notwendigkeiten abzuholen, Stufendiagnostik zu betreiben, Verschlimmerung und Komplikationen des Leidens zu verhindern, Doppeluntersuchungen und unsinnige Indikationen zu vermeiden, auch im Einzelfall gezielte Überführungen in eine erweiterte, spezialisierte Diagnostik und Therapie zu veranlassen und eine dem Gesamtkonzept entsprechende, gut etablierte Zusammenarbeit mit den Kliniken bzw. verschiedenen Fachgebieten zu führen, in der Praxis dennoch viel zu kurz. Die Teilnahme an entsprechenden Weiterbildungen und folglich die praktische Umsetzung der validen Methoden in Diagnostik und Therapie im Sinne eines Qualitätsstandards ist in allen Aktionsbereichen, so auch im niedergelassenen Bereich gefordert.Due to demographical changes the frequency of chronic diseases in the human populations of industrialised countries increased drastically over the past years. Recently also pelvic floor disorders, such as incontinence, became of higher interest of health care politics and economics and were recognized as so called widespread diseases. Being afflicted with a great taboo the most focused target is to initially take away the stigma of theses diseases. This study aims to shed light on the current concepts of diagnostics concerning pelvic floor disorders in German gynaecological surgeries. To this end the sight of general practicing gynaecologists on their role in determination, initiation of therapies and aftertreatment was to be investigated employing a questionnaire of 41 queries. The return rate of 31 % indicates a general interest in the therapeutic management of pelvic floor disorders. However in the majority of considered surgeries the number of patients with incontinence is still enormously underestimated regarding it being a world-wide political recognised widespread disease. In addition the individual data significantly vary, indicating the requirement of changes in the tenor of general practicing gynaecologists in order to establish a still missing clinical picture of pelvic floor disorders as central diseases with interdisciplinary aspects. Nevertheless the majority of gynaecologists state to broadly cover the required diagnostics and therapies, including the interdisciplinary collaboration and support of hospital treatment. Thus, an initial paradigm shift in the handling of such huge groups of patients is recognisable. This tendency becomes obviously especially with younger colleagues. Moreover, this study shows that economical and social aspects, such as age of the practicing gynaecologist, future concepts and mainly the current changes in health care politics in Germany strongly affect the individual stance on the general issue. Hence, in gynaecological surgeries the demand for a general standard ensuring an adequate and individual treatment for each patient with pelvic floor disease, including stepwise diagnostics, the avoidance of aggravation, difficulties as well as counterproductive examinations, the individual handover to hospital treatment, specialised diagnostics and therapies and a well-established interdisciplinary collaboration, is still not satisfying. However the majority of considered colleagues tends to favour and support such a basic concept