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Aims The Irish DNA Atlas is a DNA collection being assembled with the aim of describing the fine-scale population structure in Ireland. Understanding such structure can inform on optimal design of clinical genetic studies as well as the history of the Irish population. We will present an overview of and the preliminary findings from the study. Methods We are recruiting individuals with all eight greatgrandparents born in Ireland, within 30 kilometres of each other. Participants are asked to complete a detailed birth-brief, which records place and date of birth of three generations of ancestors. We also collect some basic health-related details. DNA is extracted from a saliva sample. We have genotyped using an Illumina OmniExpressdense SNP genotyping platform. We present a number of analyses designed to visualise genetic structure, including; Principle Component, ADMIXTURE, and Runs of Homozygosity analysis. Results To date we have recruited 162 participants. The mean great-grandparental area is 32 kilometres, with an average greatgrandparental date of birth of 1850. Therefore the individuals in the Atlas provide insight to the genetic landscape of Ireland before significant movement of people from the 20th century onwards. An analysis of dense genotyping data from 142participants shows that the Atlas participants cluster closely with British individuals in a Europe wide PCA, but present different ancestral population components when compared with British, and other European populations. Irish individuals also present slightly higher levels of homozygosity relative to mainland European levels. PCA targeted at specific areas of interest within Ireland also hint at fine-scale substructure. Conclusion Ireland shows typical features of a homogenous population, well suited to the study of rare variation in disease risk., Background Progress in diagnostic and therapeutic strategies in medicine is dependent upon high-quality biomedical research. Translation of research findings into the clinic relies on patient participation in innovative clinical trials. We investigated attitudes to genetic research in Ireland, in particular with respect to commercial and financial implications. Methods A multi-centre cross-sectional survey study was performed. Consecutive patients attending four out-patient clinics were asked to complete paper-based questionnaires. An electronic version of the same questionnaire was created on Survey Monkey with a link made public on a social media website for a period of 24 hours. Data was analysed using SPSS. Results 351 questionnaires were completed (99 paper, 252 electronic). The majority of respondents were female (n = 288, 82%), and highly educated, with 244 (70%) attending college/university. Most participants supported genetic research (267, 76%), more frequently for common diseases (274, 78%) than rare disorders (204, 58%, p < 0.001, x2). 103 (29%) had participated in scientific research, and 57(16%) had donated material to a bio-bank. The majority (n = 213, 61%) would not support research with potential financial/commercial gain. 106(30%) would decline to participate in research if researchers would benefit financially, compared to 49(14%) if the research was supported by a pharmaceutical company, (p < 0.001, x2). Respondents would provide buccal samples (258, 74%) more readily than tissue (225, 64%) or blood (222, 63%). Conclusion A high level of support for genetic research exists among the Irish population, but active participation is dependent upon a number of factors, notably, type of biological material required, frequency of the disease in question, and commercial interest of the researchers., Introduction Although the etiology of schizophrenia (SZ) is largely unknown, it is increasingly clear that genetic and environmental interactions contribute to cognitive deficits associated with this disorder. Recent Genome wide association studies (GWAS) have indicated a link between SZ and immune dysregulation, especially genetic mutations related to the major histocompatibility complex (MHC). Cognitive deficits are core features of Schizophrenia and related disorders, which relate to genetic risk. This study aims to explore the relationship between MHC risk variants for SZ and cognitive deficits, while also relating findings to brain activity. Methods To test if MHC risk variants impair cognition, ANCOVA analysis is performed on genetics data previously collected in a GWAS. Cognition measures are compared in groups with and without MHC genetic risk, in a population of SZ sufferers and healthy controls. Functional MRI imaging will also be performed to test if genetic risk relates to altered neural activity. Results Preliminary analyses suggest that MHC risk variants contribute to impairments in cognition in domains of social cognition, IQ and attention. Further analysis will be performed to test for environmental mediators of this relationship, looking at cannabis use and urbanicity. BOLD fMRI will also be used to test for a relationship between MHC risk and altered neural activity, using MATLAB SPM. Conclusions The MHC genetic variant may serve as a significant risk marker for schizophrenia, and further elucidate etiology of this neurodevelopmental disorder. Future studies on neurobiology of social cognition, and greater knowledge of genetic risk may establish targets for interventions., Aim To create a bioluminescence mouse model which expresses firefly luciferase in the corneal epithelium to assess gene editing and gene silencing for the cornea. Methods A gene targeting vector was generated where the Krt12 coding sequence in and the splice donor site of exon 1 were replaced with a transgene cassette containing a luc2-Multiple Targeting Cassette (MTC) gene fusion. The vector was transfected by electroporation into the Taconic Artemis C57BL/6N Tac ES cell line. Homologous recombinant clones were isolated and validated, and the mice bred with luc2-positive/ PuroR-negative offspring used for colony establishment. To visualise the expression of luc2 within the corneal epithelium, luciferin substrate diluted in viscotears was applied to the front of the eye and then luciferase expression was imaged and assessed using a Xenogen IVIS Lumina Imager and LivingImage 3.2 software. Intrastromal injection of siGlo siRNA was used to determine the localisation of siRNA within the corneal epithelium and then the established mouse model was treated with either native or Accell “self-delivery” siRNA. Results The Accell “self-delivery” siRNA induced potent sustained allele specific silencing for 7 days, while native versions of siRNA resulted in significant knock-down for 1 day only (p < 0.05). We have created and validated a bioluminescence mouse model and have utilised it to assess siRNA in vivo. This mouse model coupled with the Lumina imager will allow us to assess topical delivery of gene therapies to the ocular surface allowing validation for future translation to clinical use., Background Methylation of DNA sequences at promoters, CpG islands and other elements plays a vital role in regulating gene activity. In human, loss of methylation is known to play a causative role in imprinting disorders and in inappropriate germline gene expression in cancers. While in mouse, loss of function mutants have given great insight into the targets of methylation, functional studies in human have been largely limited to cancer cells and more recently stem cells, not normal adult cells. Methods Stable knockdowns of the maintenance methyltransferase DNMT1 were generated in normosomic hTERT-immortalised adult fibroblasts. Genome-wide methylation levels were assayed using the Illumina 450K bead array. Results were analysed using RnBeads and Galaxy. Locusspecific methylation was verified using pyrosequencing and clonal analysis. Validation was achieved using transient siRNA. Results Loss of function was poorly tolerated and all clonally-expanded cell lines had spontaneously restored DNMT1 levels by silencing of the shRNA. Evidence for a genome-wide methylation erasure event followed by a wave of remethylation could be clearly traced. Gene bodies and the shores of CpG islands showed the clearest loss of methylation overall. While most CpG islands are normally unmethylated and so unaffected, both imprints and germline genes fall into the rarer category of normally methylated islands: of these two, lasting loss of methylation was much more common among imprints than germline genes. Conclusions 1: transient loss of methylation is poorly tolerated; 2: a robust mechanism for remethylation exists even in adult cells; 3: aberrant remethylation is frequent on recovery and 4: Imprints are particularly sensitive., Background Dihydrofolate reductase (DHFR) is essential for the conversion of folic acid to active folate needed for one-carbon metabolism. Common genetic variation within DHFR is restricted to the noncoding regions and previous studies have focused on a 19 bp deletion/insertion polymorphism (rs70991108) within intron 1. Reports of an association between this polymorphism and blood folate biomarker concentrations are conflicting. Objective We aimed to evaluate whether the DHFR 19bp deletion/ insertion polymorphism affects circulating folate biomarkers in the largest cohort to address this question to date. Methods Young healthy Irish individuals (n= 2,507) between 19 to 36 years old were recruited between February 2003 and 2004. Folic acid intake from supplements and fortified foods was assessed using a customized food intake questionnaire. Concentrations of serum folate and vitamin B-12, red blood cell (RBC) folate and plasma total homocysteine (tHcy) concentration were measured. Data were analysed using linear regression models. Results Folic acid intake was positively associated with serum (P 326μg folic acid/day; P = 0.96). A non-significant trend towards lower RBC folate by genotype (P = 0.09) was observed in the lowest folic acid intake quintile (0 – 51 μg/day). Conclusion In this cohort of young healthy individuals the DHFR 19bp deletion allele does not significantly affect circulating folate status, irrespective of folic acid intake. Our data rule out a strong functional effect of this polymorphism on blood folate concentrations.

A method that uses liquid chromatography with tandem mass spectrometry (LC/MS/MS) has been developed for the highly sensitive and specific determination of amnesic shellfish poisoning toxins, diarrhetic shellfish poisoning toxins, and other lipophilic algal toxins and metabolites in shellfish. The method was subjected to a full single-laboratory validation and a limited interlaboratory study. Tissue homogenates are blended with methanol-water (9 + 1), and the centrifuged extract is cleaned up with a hexane wash. LC/MS/MS (triple quadrupole) is used for quantitative analysis with reversed-phase gradient elution (acidic buffer), electrospray ionization (positive and negative ion switching), and multiple-reaction monitoring. Ester forms of dinophysis toxins are detected as the parent toxins after hydrolysis of the methanolic extract. The method is quantitative for 6 key toxins when reference standards are available: azaspiracid-1 (AZA1), domoic acid (DA), gymnodimine (GYM), okadaic acid (OA), pectenotoxin-2 (PTX2), and yessotoxin (YTX). Relative response factors are used to estimate the concentrations of other toxins: azaspiracid-2 and -3 (AZA2 and AZA3), dinophysis toxin-1 and -2 (DTX1 and DTX2), other pectenotoxins (PTX1, PTX6, and PTX11), pectenotoxin secoacid metabolites (PTX2-SA and PTX11-SA) and their 7-epimers, spirolides, and homoYTX and YTX metabolites (45-OHYTX and carboxyYTX). Validation data have been gathered for Greenshell mussel, Pacific oyster, cockle, and scallop roe via fortification and natural contamination. For the 6 key toxins at fortification levels of 0.05–0.20 mg/kg, recoveries were 71–99% and single laboratory reproducibilities, relative standard deviations (RSDs), were 10–24%. Limits of detection were

Background: Neuropeptide S (NPS) and its receptor (NPSR) have been implicated in the mediation of anxiolytic-like behavior in rodents. However, little knowledge is available to what extent the NPS system is involved in depression-related behaviors. The aim of the present work was to characterize the effects of centrally administered NPS on depression- and anxiety-related behaviors, using a well validated animal model of depression, the Flinders Sensitive Line (FSL) rats and their controls the Flinders Resistant Line (FRL). Methods: Male and female were tested. Seven days following insertion of cannula, 0.25 or 1.0 nmol NPS, or vehicle/5 ml were infused into the lateral ventricle. 45 min after NPS infusion animals were tested on elevated plus maze (EPM). Five days later the animals were subjected to the two-day forced swim test (FST); NPS or vehicle were injected 45 min before the second day FST. In selected animals effect of NPS on home cage activity was explored. Finally, brains from separate groups of naive animals were harvested; hippocampi, amygdalae and PVN punched out, and mRNA transcripts measured with the real-time quantitative polymerase chain reaction (rt-qPCR). Results: The most salient findings were: (1) NPS increased in a dosedependent fashion the percent time spent in the open arms and the number of full entries in the FSL rat (p'so0.01), while the effects in the FRL were only marginal; (2) In contrast to altered behavior in the EPM, behavior in the FST was not affected by NPS; (3) In the home cage, NPS increased locomotion in a dose dependent fashion in the FSL; (4) rt-qPCR showed that NPSR expression was lower in amygdalae in the FSL; no other region or strain differences were found. Discussion: Baseline depression-like behavior was markedly higher in the FSL compared to FRL rats while no difference in the anxiety-like behavior was observed. These findings confirm the utility of the FSL as a model of depression useful in exploration of neurobiological correlates both of depression and those discriminating between depression and anxiety endophenotypes. NPS had marked anxiolytic effects but did not modify the depression-like behavior. These results clearly separate effects of NPS from those of the classical antidepressants (tricyclics and SSRIs) which are also anxiolytic, and indicate that NPS agonists could be useful as selective anxiolytic drugs.

OBJECTIVE: To validate continuous glucose monitoring (CGM) in children and adolescents with cystic fibrosis. RESEARCH DESIGN AND METHODS: Paired oral glucose tolerance tests (OGTTs) and CGM monitoring was undertaken in 102 children and adolescents with cystic fibrosis (age 9.5-19.0 years) at baseline (CGM1) and after 12 months (CGM2). CGM validity was assessed by reliability, reproducibility, and repeatability. RESULTS: CGM was reliable with a Bland-Altman agreement between CGM and OGTT of 0.81 mmol/l (95% CI for bias +/- 2.90 mmol/l) and good correlation between the two (r = 0.74-0.9; P < 0.01). CGM was reproducible with no significant differences in the coefficient of variation of the CGM assessment between visits and repeatable with a mean difference between CGM1 and CGM2 of 0.09 mmol/l (95% CI for difference +/- 0.46 mmol/l) and a discriminant ratio of 13.0 and 15.1, respectively. CONCLUSIONS: In this cohort of children and adolescents with cystic fibrosis, CGM performed on two occasions over a 12-month period was reliable, reproducible, and repeatable.

Copyright © 2003 P. Hess et al. Released with the permission of UNESCO IOC from http://unesdoc.unesco.org/images/0021/002189/218973E.pdf, During 2001, the Marine Institute has extended its range of chemical tests to include the analysis of DSP toxins by Liquid Chromatography coupled to Mass Spectrometry (LC-MS). Thus the range of compounds determined extends from domoic acid over DSP compounds (okadaic acid and DTXs) to azaspiracids (AZAs). These tests complement the mouse bioassay, which is the current reference method for lipophilic toxins within the European Community. The development and performance characteristics of the LC-MS method are discussed. Isomer patterns and interspecies differences are discussed as well as local trends in time and variability at one production site at a given time. Comparison of the LC-MS results with the results from the mouse bioassay showed good agreement (93%), and a small but significant number of discrepancies (7%). Overall, the chemical testing has proven to be an invaluable tool in the assessment of shellfish toxicity in Ireland. Lacks of standards and reference materials are discussed as well as the need for further research into the equivalence of methods.