Intelligence is highly heritable and a major determinant of human health and well-being. Recent genome-wide meta-analyses have identified 24 genomic loci linked to variation in intelligence, but much about its genetic underpinnings remains to be discovered. Here, we present a large-scale genetic association study of intelligence (n = 269,867), identifying 205 associated genomic loci (190 new) and 1,016 genes (939 new) via positional mapping, expression quantitative trait locus (eQTL) mapping, chromatin interaction mapping, and gene-based association analysis. We find enrichment of genetic effects in conserved and coding regions and associations with 146 nonsynonymous exonic variants. Associated genes are strongly expressed in the brain, specifically in striatal medium spiny neurons and hippocampal pyramidal neurons. Gene set analyses implicate pathways related to nervous system development and synaptic structure. We confirm previous strong genetic correlations with multiple health-related outcomes, and Mendelian randomization analysis results suggest protective effects of intelligence for Alzheimer's disease and ADHD and bidirectional causation with pleiotropic effects for schizophrenia. These results are a major step forward in understanding the neurobiology of cognitive function as well as genetically related neurological and psychiatric disorders.
ehaviors related to self-regulation, such as substance use disorders or antisocial behaviors, have far-reaching consequences for affected individuals, their families, communities and society at large 1,2 . Collectively, this group of correlated traits are classified as externalizing 3 . Twin studies have demonstrated that externalizing liability is highly heritable (~80%) 4,5 . To date, however, no large-scale molecular genetic studies have utilized the extensive degree of genetic overlap among externalizing traits to aid gene discovery, as most studies have focused on individual disorders 6 . For many high-cost, high-risk behaviors with an externalizing component-opioid use disorder and suicide attempts 7 being salient examples-there are limited genotyped cases available for gene discovery 8,9 .A complementary strategy to the single-disease approach is to study the shared genetic architecture across traits in multivariate analyses, which boosts statistical power by pooling data across
Purpose – The purpose of this study is to identify an appropriate factor structure that may be utilized to effectively measure a hotel’s performance relative to service quality in a mid-scale setting. Customer perceptions of service quality in mid-scale hotels have largely been ignored; the focus of researchers has been the upscale (4-star) and luxury (5-star) segments. Design/methodology/approach – A 27-item questionnaire is utilized to measure service quality with an initial sample size of over 2,500 respondents. Principle component analysis is utilized to determine the factor structure and regression analysis to determine which factors may serve as predictors of a hotel’s ability to meet customers’ expectations and to provide value. Findings – A three-dimensional model emerged from the data, consistent with the theorizing of Rust and Oliver (1994), which includes the service product, service delivery and service environment. The service environment is the strongest predictor of a hotel’s ability to meet guests’ expectations and to provide guests with value within this context, which is inconsistent with findings in upscale and luxury hotels. Research limitations/implications – The generalizability of this research may be challenged, as the study was conducted within the context of an oceanfront resort destination dominated by leisure travelers; however, the study may be replicated in additional settings to determine if a similar bundling of service quality attributes occurs in other mid-scale settings including business hotels, as well as economy hotels. Practical implications – A three-factor model may be more appropriate for assessing service quality in a mid-scale (3-star) environment. In this setting, the service environment and service product may be more important measures of service quality than service delivery. This is an important finding, as many mid-scale and select-service, as well as new mid-scale, lifestyle hotel concepts, attempt to drive profitability by deemphasizing service delivery or by utilizing technology to facilitate service delivery. These findings may also assist operators of mid-scale hotels in improving guests’ perceptions of quality, which has been found to increase perceived value and may positively influence purchase or revisit intentions (Kashyap and Bojanic, 2000). Originality/value – Service quality research has been conducted, almost exclusively, in first-class (4-star) and luxury (5-star) hotels, while the majority of hotels do not fall into these categories. Although guest expectations relative to service quality may be lower in more moderately priced, mid-scale hotels, service quality remains a critical variable that influences a guest’s decision to return or recommend a hotel to others. Many travelers now utilize online reviews to minimize purchase risk by seeking information relative to service quality when selecting a hotel. Consequently, it is more important than ever that service quality is understood in hotels at all service levels. The present research contributes to filling this gap in the literature.
Background and Objectives There have been remarkable advances in understanding genetic influences on complex traits; however, individuals of African descent have been underrepresented in genetic research. Methods We review the limitations of existing genetic research on alcohol phenotypes in African Americans (AA) including both twin and gene identification studies, possible reasons for underrepresentation of AAs in genetic research, the implications of the lack of racially diverse samples, and special considerations regarding conducting genetic research in AA populations. Results There is a marked absence of large-scale AA twin studies so little is known about the genetic epidemiology of alcohol use and problems among AAs. Individuals of African descent have also been underrepresented in gene identification efforts; however, there have been recent efforts to enhance representation. It remains unknown the extent to which genetic variants associated with alcohol use outcomes in individuals of European and African descent will be shared. Efforts to increase representation must be accompanied by careful attention to the ethical, legal, and social implications of genetic research. This is particularly true for AAs due to the history of abuse by the biomedical community and the persistent racial discrimination targeting this population. Conclusions and Scientific Significance Lack of representation in genetic studies limits our understanding of the etiological factors that contribute to substance use and psychiatric outcomes in populations of African descent and has the potential to further perpetuate health disparities. Involving individuals of diverse ancestry in discussions about genetic research will be critical to ensure that all populations benefit equally from genetic advances.
As psychiatric genetics enters an era where gene identification is finally yielding robust, replicable genetic associations and polygenic risk scores, it is important to consider next steps and delineate how that knowledge will be applied to ultimately ameliorate suffering associated with substance use and psychiatric disorders. Much of the post-genome-wide association study discussion has focused on the potential of genetic information to elucidate the underlying biology and use this information for the development of more effective pharmaceutical treatments. In this review we focus on additional areas of research that should follow gene identification. By taking genetic findings into longitudinal, developmental studies, we can map the pathways by which genetic risk manifests across development, elucidating the early behavioral manifestations of risk, and studying how various environments and interventions moderate that risk across developmental stages. The delineation of risk across development will advance our understanding of mechanism, sex differences and risk and resilience processes in different racial/ethnic groups. Here, we review how the extant twin study literature can be used to guide these efforts. Together, these new lines of research will enable us to develop more informed, tailored prevention and intervention efforts.
Assessing educational outcomes has been an ongoing activity for higher education over the past several years. This concern is important for business educators as well. Regardless of any problems institutions have experienced, there is definitely a need to continue for many reasons: e.g., mandates by state legislatures, accreditation bodies and others, and its potential as an input into strategic planning. Thus far, assessment activities have consisted of a proliferation of methodologies ranging from student portfolio analysis to standardized testing. This paper specifically examines the use of importance-performance analysis for an evaluation of the business core curriculum, as well as some differences among major areas of study, at two distinct points in time.
This review offers an update on research conducted with FinnTwin12 (FT12), the youngest of the three Finnish Twin Cohorts. FT12 was designed as a two-stage study. In the first stage, we conducted multiwave questionnaire research enrolling all eligible twins born in Finland during 1983–1987 along with their biological parents. In stage 2, we intensively studied a subset of these twins with in-school assessments at age 12 and semistructured poly-diagnostic interviews at age 14. At baseline, parents of intensively studied twins were administered the adult version of the interview. Laboratory studies with repeat interviews, neuropsychological tests, and collection of DNA were made of intensively studied twins during follow-up in early adulthood. The basic aim of the FT12 study design was to obtain information on individual, familial and school/neighborhood risks for substance use/abuse prior to the onset of regular tobacco and alcohol use and then track trajectories of use and abuse and their consequences into adulthood. But the longitudinal assessments were not narrowly limited to this basic aim, and with multiwave, multirater assessments from ages 11 to 12, the study has created a richly informative data set for analyses of gene–environment interactions of both candidate genes and genomewide measures with measured risk-relevant environments. Because 25 years have elapsed since the start of the study, we are planning a fifth-wave follow-up assessment.
Individuals with autism spectrum disorder (ASD) present difficulties in forming relations among items and context. This capacity for relational binding is also involved in spatial navigation and research on this topic in ASD is scarce and inconclusive. Using a computerised version of the Morris Water Maze task, ASD participants showed particular difficulties in performing viewpoint independent (allocentric) navigation, leaving viewpoint dependent navigation (egocentric) intact. Further analyses showed that navigation deficits were not related to poor visual short-term memory or mental rotation in the ASD group. The results further confirm the need of autistic individuals for support at retrieval and have important implications for the design of signposts and maps.Electronic supplementary materialThe online version of this article (10.1007/s10803-018-3465-5) contains supplementary material, which is available to authorized users.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
334 Leonard St
Brooklyn, NY 11211
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.