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As part of the International Multi-centre ADHD Gene (IMAGE) project we have completed an affected sibling pair study of 142 narrowly defined DSM-IV combined type ADHD proband-sibling pairs. We found suggestive linkage on chromosomes 9 and 16 with non-parametric multipoint peak LOD scores of 2.13 and 3.1 respectively. There have been several previous ADHD linkage scans. The UCLA study (Fisher et al. 2002; Ogdie et al. 2004; Ogdie et al. 2003), the Dutch study (Bakker et al. 2003), the German study (Hebebrand et al. 2006) and the MGH Study (Faraone et al., submitted) applied the affected sib pair (ASP) strategy; the Columbian study used extended pedigrees ascertained from a population isolate (Arcos-Burgos et al. 2004). No linkage was observed on the most established ADHD linked genomic regions from these studies on 5p and 17p. The highest multipoint nonparametric linkage signal on chromosome 16q23 at 99 cM (LOD=3.1) overlapped with data published from UCLA (LOD>1, ~95cM) and Holland (LOD>1, ~100cM). The second highest peak in this study was on chromosome 9q22 at 90cM (LOD=2.13). Both the UCLA study and the German study also found some evidence of linkage at almost the same location (UCLA LOD=1.45 at 93cM; German LOD=0.68 at 100cM). The overlap of the two main peaks from this study with those from previous studies suggests that true loci linked to ADHD may lie within these regions.

Background:Attention-deficit hyperactivity disorder (ADHD) is one of the most common and highly heritable child psychiatric disorders. There is strong evidence that children with ADHD show slower and more variable responses in tasks such as Go/Nogo tapping aspects of executive functions like sustained attention and response control which may be modulated by motivational factors and/or state-regulation processes. The aim of this study was (1) to determine if these executive functions may constitute an endophenotype for ADHD; (2) to investigate for the first time whether known modulators of these executive functions may also be familial; and (3) to explore whether gender has an impact on these measures.Methods:Two hundred and five children with ADHD combined type, 173 nonaffected biological siblings and 53 controls with no known family history of ADHD were examined using a Go/Nogo task in the framework of a multi-centre study. Performance-measures and modulating effects of event-rate and incentives were examined. Shared familial effects on these measures were assessed, and the influence of gender was tested.Results:Children with ADHD responded more slowly and variably than nonaffected siblings or controls. Nonaffected siblings showed intermediate scores for reaction-time variability, false alarms and omission errors under fast and slow event-rates. A slower event-rate did not lead to reduced performance specific to ADHD. In the incentive condition, mean reaction-times speeded up and became less variable only in children with ADHD and their nonaffected siblings, while accuracy was improved in all groups. Males responded faster, but also committed more false alarms. There were no interactions of group by gender.Conclusions:Reaction-time variability and accuracy parameters could be useful neuropsychological endophenotypes for ADHD. Performance-modulating effects of incentives suggested a familially driven motivational dysfunction which may play an important role on etiologic pathways and treatment approaches for ADHD. The effects of gender were independent of familial effects or ADHD-status, which in turn suggests that the proposed endophenotypes are independent of gender.

This paper examines perceptions regarding rural male suicide and the preventative services available in Co. Kilkenny to combat the problem. For every four male suicides, there is one female suicide. The problem is becoming a rural rather than an urban one. The research set out to identify gaps in services and existing policies in addressing suicide among young rural men. Data were obtained from interview with the service providers and also from focus group discussions with young rural Kilkenny men. Total participants in the focus groups were 15 young men. Limitations to this study centred around the difficulty of organising young men to take part in the focus discussion groups. Many official organisations in Co. Kilkenny were approached but no focus group was forthcoming. The one official group that took part was through Macra na Feirme. The other three focus groups that were gathered came from personal contacts. However, even through these channels many potential groups in the end did not materialise and for the groups that did materialise many of the young men did not turn up. Overall the general feedback from people in their resistance to coming together was that the topic was a deterrent to them. The research shows that none of the service providers have a specific focus on the problem of suicide among young rural males and that a National Prevention Strategy is yet to be presented by the National Task Force on Suicide. The prevention services available at the moment are not seen as relevant to young men. They need to become more acceptable especially to those in the high-risk categories. More research needs to be conducted to find the reasons why young rural men are committing suicide so that suitable service responses can be created.