The phenotypic and genotypic relation between working memory speed and capacity

This study examined the phenotypic and genotypic relationship between working memory speed (WMS) and working memory capacity (WMC) in 12-year-old twins and their siblings (N = 409). To asses WMS all children performed a reaction time task with three memory loads from which a basic mental speed measure and the derived slope were used. WMC was measured with two subtests of the WISC-R, namely Arithmetic and Digit Span. The phenotypic correlations among the WMS and WMC indices were around − 0.30. Heritabilities for all variables ranged from 43% to 56%. Structural equating modelling revealed that a model with two genetic factors, representing WMS and WMC, which were correlated (− 0.54) fitted the data best, indicating that WMS and WMC are partly mediated by the same set of genes and partly by separate sets of genes. When general IQ was simultaneously analysed with the data the correlation between the genetic factors for WMS and WMC decreased (− 0.25), but was still significant. This means that  50% of the genetic correlation between WMS and WMC is explained by IQ.     

A New Definition of Genetic Counseling: National Society of Genetic Counselors’ Task Force Report

The Genetic Counseling Definition Task Force of the National Society of Genetic Counselors (NSGC) developed the following definition of genetic counseling that was approved by the NSGC Board of Directors: Genetic counseling is the process of helping people understand and adapt to the medical, psychological and familial implications of genetic contributions to disease. This process integrates the following: •Interpretation of family and medical histories to assess the chance of disease occurrence or recurrence. •Education about inheritance, testing, management, prevention, resources and research. •Counseling to promote informed choices and adaptation to the risk or condition. The definition was approved after a peer review process with input from the NSGC membership, genetic professional organizations, the NSGC legal counsel, and leaders of several national genetic advocacy groups.     

DNA-sequence patenting: National Society of Genetic Counselors (NSGC) position paper

In November 2000, the Genetic Services Committee of the National Society of Genetic Counselors (NSGC) convened a working group to draft a position paper on patenting of DNA-sequences. The mandate of the group was to produce general position statements that support the perspective and needs of consumers of DNA-based genetic tests and therapies (our patients and their families) and participants in DNA-based genetic research. After review and discussion of the literature on DNA-sequence patenting issues, the working group drafted position statement points that support current United States Patent and Trademark Office (USPTO) guidelines; broad licensing of DNA-sequence patents; nonenforcement of DNA-sequence patents in noncommercial research; reasonable royalty rates; an informed consent process for research participants that discloses whether they can share in any financial rewards relating to the project; the development of guidelines for licensing of DNA-sequence patents; and the establishment of oversight organizations to monitor licensing of DNA-sequence patents. These position statements were approved by the NSGC Board of Directors in the fall of 2001.     

Were the Victorians cleverer than us? The decline in general intelligence estimated from a meta-analysis of the slowing of simple reaction time

The Victorian era was marked by an explosion of innovation and genius, per capita rates of which appear to have declined subsequently. The presence of dysgenic fertility for IQ amongst Western nations, starting in the 19th century, suggests that these trends might be related to declining IQ. This is because high-IQ people are more productive and more creative. We tested the hypothesis that the Victorians were cleverer than modern populations, using high-quality instruments, namely measures of simple visual reaction time in a meta-analytic study. Simple reaction time measures correlate substantially with measures of general intelligence (g) and are considered elementary measures of cognition. In this study we used the data on the secular slowing of simple reaction time described in a meta-analysis of 14 age-matched studies from Western countries conducted between 1889 and 2004 to estimate the decline in g that may have resulted from the presence of dysgenic fertility. Using psychometric meta-analysis we computed the true correlation between simple reaction time and g, yielding a decline of − 1.16 IQ points per decade or − 13.35 IQ points since Victorian times. These findings strongly indicate that with respect to g the Victorians were substantially cleverer than modern Western populations.     

The general factor of personality: Substance or artefact?

While it is now widely recognized that a general factor (GFP) can be extracted from most personality data, this finding has been subject to numerous critiques: (1) that the GFP is an artefact due to socially desirable responding; (2) that it is factorially indeterminate; (3) that it can be more parsimoniously modelled using blended variables; (4) that it shows less genetic variance due to dominance than should be true of a fitness trait; (5) that it correlates more weakly with g than would be predicted from Life History theory; (6) that it cannot be recovered across personality inventories. We present new evidence and argument to show that each of these critiques is open to reasonable doubt.     

Schizotypy,cognitive performance,and genetic risk for schizophrenia in a non-clinical population

Schizophrenia risk alleles are expected to mediate effects on cognitive task performance, and aspects of personality including schizotypy, in nonclinical populations. We investigated how 32 of the best-validated schizophrenia risk alleles, singly and as summed genetic risk, were related to measures of schizotypal personality and measures of two aspects of cognitive performance, verbal skills (vocabulary) and visual-spatial skills (mental rotation), in healthy individuals. Summed genetic risk score was not associated with levels of total schizotypy or its three main subscales. Similarly, genotypic variation at none of the individual risk loci was related to cognitive performance measures, after correction for multiple tests. Higher overall genetic risk score was, however, associated with lower performance on the mental rotation test in males, with a broad set of loci contributing to this effect. These results imply that there is a lack of linear, genetically-based continuity connecting schizotypal cognition with the expression of schizophrenia itself, and indicate that, for males, higher genetic risk of schizophrenia exerts negative effects on visual-spatial skills, as measured by mental rotation.     

Genetic Indigenisation in ‘The People of the British Isles’

In 2007, Channel 4 screened Face of Britain, a documentary about the genetic mapping of Britain. Face of Britain promised to reveal ‘who we really are’ by tracing genetic links back to ancient Celts, Anglo-Saxons, Vikings and Normans. This article situates Face of Britain within the wider racial and national politics that it is invariably caught up in, and examines how ‘race’ and racial thinking are reconfigured in ways that are both ‘old’ and ‘new’. Face of Britain constitutes an interesting case study to examine how ideas of indigeneity are produced and naturalised in scientific discourses and practices. Here, indigeneity is mobilised through three sub-narratives: the ‘vanishing indigene’; the promise of facial recognition; and DNA and national relatedness. The analysis reveals how some people of the British Isles are naturalised as indigenous by virtue of their ancestral presence in this land through a combination of genetic and photographic technologies. In short, blood and soil are intertwined, with genes as mediators between ancestors and contemporary inhabitants of Britain. Furthermore, the invisible genetic connection is made visible through the creation of ‘average faces of Britain’, which is considered here as a contemporary version of physiognomy. In conclusion, Face of Britain testifies to the reconfiguration of ‘racial thinking’ in contemporary science, through what ultimately amounts to the genetic indigenisation of white Britons. Consequently, this study lends itself to racialised politics of land claims that resonate with, but are different from, indigenous politics in other contexts, namely with regards to the relationship to whiteness.     

Personhood: Elusive But Not Illusory

Bioethics as a field has been fortunate that its values and concerns have mirrored the values and concerns of society. In light of the September 11th attacks, it is possible that we are witnessing the beginning of a transition in American culture, one fraught with implications for bioethics. The emphasis on autonomy and individual rights may come to be tempered by greater concern over the collective good. Increased emphasis on solidarity over autonomy could greatly alter public response to research abuses aimed at defense from bioterrorism, to privacy of genetic information, and to control of private medical resources to protect the public health.     

Perception of risk in genetic counseling

Abstract

Genetic counseling is a psychological process of communicating and perceiving information about risks. As such, it is important to assess how information is understood by counselees and how psychological factors affect risk perception. Subjects were 76 patients at a genetic clinic whose understanding of genetic counseling was assessed, along with their motivation and way of thinking about risks. Results indicated that subjective interpretations of recurrence risks are better predictors of their reproductive intentions than the “objective” risks. Also, specific cognitive and motivational factors appear to explain much of the variance in risk perception in genetic counseling. The results have important implications for how counseling is conducted, as well as for theoretical issues about cognitive processes.     

Effects of chronic cocaine administration on spatial learning and hippocampal spine density in two genetically different strains of rats

Lewis and Fischer-344 rats have been proposed as an addiction model because of their differences in addiction behaviour. It has been suggested that drug addiction is related to learning and memory processes and depends on individual genetic background. We have evaluated learning performance using the eight-arm radial maze (RAM) in Lewis and Fischer-344 adult rats undergoing a chronic treatment with cocaine. In order to study whether morphological alterations were involved in the possible changes in learning after chronic cocaine treatment, we counted the spine density in hippocampal CA1 neurons from animals after the RAM protocol. Our results showed that Fischer-344 rats significantly took more time to carry out test acquisition and made a greater number of errors than Lewis animals. Nevertheless, cocaine treatment did not induce changes in learning and memory processes in both strains of rats. These facts indicate that there are genetic differences in spatial learning and memory that are not modified by the chronic treatment with cocaine. Moreover, hippocampal spine density is cocaine-modulated in both strains of rats. In conclusion, cocaine induces similar changes in hippocampal neurons morphology that are not related to genetic differences in spatial learning in the RAM protocol used here.