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This chapter explores the approach of the CJEU and the ECtHR to the highly contentious topic of surrogacy in order to unravel the understanding of motherhood endorsed by these two European courts. It shows that legal motherhood continues to be tied to gestation and birth, thus placing intended mothers in a precarious legal position, especially compared to intended (genetic) fathers. As part of its effort to explain this gender imbalance, the chapter uses the experience of surrogacy as a window for a broader discussion on the gender of legal fictions governing the attribution of parenthood. Whilst the rule mater semper certa est remains one of the most immutable facts of European family laws, legal systems have generally demonstrated a certain flexibility and attention to context in determining legal fatherhood, at times departing from the marital presumption. The chapter argues that this differential attitude reflects a long-standing socio-legal resistance to breaking the continuum gestation-motherhood-caregiving, and aligns with the gendered and higher expectations that legal systems place on mothers compared to fathers.
The paper will be looking at two Second World War texts, Olaf Stapledon’s 1944 science fiction fantasy Sirius, about the genetic modification of a sheepdog so that it becomes a superdog capable of speech and spiritual and erotic relationships; and Charles Williams’ 1945 theological fantasy All Hallow’s Eve. The novels are novels of ideas, testing theories of creative evolution and species distinctions with Stapledon, and damnation and control with Williams: both explore the death drive within the psyche in war culture, and posit the very different ways infection by Fascist politics have shaped those explorations.
Early worsening of plasma lipid levels (EWL; ≥5% change after 1 month) induced by at-risk psychotropic treatments predicts considerable exacerbation of plasma lipid levels and/or dyslipidaemia development in the longer term.
Aims
We aimed to determine which clinical and genetic risk factors could predict EWL.
Method
Predictive values of baseline clinical characteristics and dyslipidaemia-associated single nucleotide polymorphisms (SNPs) on EWL were evaluated in a discovery sample (n = 177) and replicated in two samples from the same cohort (PsyMetab; n1 = 176; n2 = 86).
Results
Low baseline levels of total cholesterol, low-density lipoprotein cholesterol (LDL-C) and triglycerides, and high baseline levels of high-density lipoprotein cholesterol (HDL-C), were risk factors for early increase in total cholesterol (P = 0.002), LDL-C (P = 0.02) and triglycerides (P = 0.0006), and early decrease in HDL-C (P = 0.04). Adding genetic parameters (n = 17, 18, 19 and 16 SNPs for total cholesterol, LDL-C, HDL-C and triglycerides, respectively) improved areas under the curve for early worsening of total cholesterol (from 0.66 to 0.91), LDL-C (from 0.62 to 0.87), triglycerides (from 0.73 to 0.92) and HDL-C (from 0.69 to 0.89) (P ≤ 0.00003 in discovery sample). The additive value of genetics to predict early worsening of LDL-C levels was confirmed in two replication samples (P ≤ 0.004). In the combined sample (n ≥ 203), adding genetics improved the prediction of new-onset dyslipidaemia for total cholesterol, LDL-C and HDL-C (P ≤ 0.04).
Conclusions
Clinical and genetic factors contributed to the prediction of EWL and new-onset dyslipidaemia in three samples of patients who started at-risk psychotropic treatments. Future larger studies should be conducted to refine SNP estimates to be integrated into clinically applicable predictive models.
There is limited information on rare spinocerebellar ataxia (SCA) variants, particularly in the Canadian population. This study aimed to describe the demographic and clinical features of uncommon SCA subtypes in Canada and compare them with international data.
Methods:
We conducted a case series and literature review of adult patients with rare SCA subtypes, including SCA5, SCA7, SCA12, SCA14, SCA15, SCA28, SCA34, SCA35 and SCA36. Data were collected from medical centers in Ontario, Alberta and Quebec between January 2000 and February 2021.
Results:
We analyzed 25 patients with rare SCA subtypes, with onset ages ranging from birth to 67 years. Infantile and juvenile-onset cases were observed in SCA5, SCA7, SCA14 and SCA34. Most patients presented with gait ataxia, with no significant differences across groups. Additional common features included saccadic abnormalities (22 of 25), dysarthria (19 of 25) and nystagmus (12 of 22, except in SCA7). Less common findings included dystonia (8 of 25), cognitive impairment (7 of 25), tremor (9 of 25) and parkinsonism (3 of 25).
Conclusion:
Our study highlights the heterogeneity of rare SCA subtypes in Canada. Ongoing longitudinal analysis will improve the understanding, management and screening of these disorders.
Newspapers expanded around 1900 to reach a wider readership, often reporting sensationalized stories about science. Attacks on the Darwinian theory of natural selection intensified, leading to claims that the theory was on its deathbed. Lamarckism remained active along with the theory of directed variation (orthogenesis), both presented as less materialistic than Darwinism. New alternatives appeared, including the ‘mutation theory’ (evolution by jumps) and genetics, which was at first presented as a threat to Darwinism rather than a supporting factor. In the 1920s a new surge of creationism in the United States intensified the attack on Darwinian materialism, culminating in the widely reported trial of J. T. Scopes. The same critiques appeared in a less muted form in Britain. The Darwinian ‘struggle for existence’ remained a source of anxiety for those who feared a potential threat to moral values and social stability.
In the 1920s and 1930s the Darwinian selection theory was linked to genetics, providing it with a secure foundation, although wider dissemination of this initiative was limited until the 1940s. Historians note that the ‘evolutionary synthesis’ was a rhetorical device to create an impression of unity, leaving the various disciplines involved still functioning independently. Radio now became an important means of disseminating science news, as in the 1959 celebrations of the centenary of the Origin of Species. The new version of Darwinism eroded the plausibility of eugenics and race theory, although these ideologies remained active in less visible forms. Popular accounts of evolutionism now stressed its open-endedness and played down the old assumption that humanity must be the inevitable outcome of progress. Julian Huxley tried to give the synthesis a moral dimension by linking it to his philosophy of humanism, but creationists saw the new initiative in science as a continuation of Darwinian materialism and renewed their attacks.
Suppose you are running a company that provides proofreading services to publishers. You employ people who sit in front of screens, correcting written text. Spelling errors are the most frequent problem, so you are motivated to hire proofreaders who are excellent spellers. Therefore, you decide to give your job applicants a spelling test. It isn’t hard: throw together 25 words, and score everyone on a scale of 0–25. You are now a social scientist, a specialist called a psychometrician, measuring “spelling ability.”
The reader should be officially informed that in this chapter I take leave of the widely accepted consensus about nature–nurture. This is not a textbook, and everything that I have said up to now has been very much my own take on things, but for the most part I have not strayed far from what most scientists would say about the intellectual history of nature and nurture. Not everyone perhaps, but most people agree that Galton was a racist, eugenics a moral and scientific failure, heritability of behavioral differences nearly universal, heritability a less than useful explanatory concept, twin studies an interesting but ultimately limited research paradigm, and linkage and candidate gene analysis of human behavior decisive failures.
Has it always been the case that living people must struggle with the moral failings of their dead ancestors, or is that a special burden that has been placed on the shoulders of citizens and scientists living in contemporary Europe and North America? Recently, the culture feels as though it is being torn apart by this question. I was taught in grade school that the United States is the greatest country in the world, the land of the free and the home of the brave, where anyone could be a millionaire or president if they put in the effort. It is hardly radical to recognize that this is less than true today and isn’t even close to true historically, especially if one is not white, Christian, and male.
Notwithstanding Galton’s admonition to count everything, counting is just a tool; it is no more science than hammering is architecture. One hundred years after Galton, Robert Hutchins remarked, contemptuously, that a social scientist is a person who counts telephone poles. The obvious way to turn counting into science is by conducting experiments, that is by manipulating nature and observing what the consequences are for whatever one is counting. Gregor Mendel, for example, was certainly a counter – he counted the mixtures of smooth and wrinkled peas in the progeny of the pea plants he intentionally crossed. What made Mendel’s work science was the intentional crossing of the plants, not the counting itself. It would have been much more difficult – perhaps impossible – to observe the segregation and independent assortment of traits by counting smooth and wrinkled peas in the wild.
Why is divorce heritable? It’s clear that it is heritable, in the rMZ > rDZ sense. I hope I have convinced you that the heritability of divorce doesn’t mean that there are “divorce genes,” or that divorce is passed down genetically from parents to children, but seriously: how does something like that happen? I am aware that my constant minimizing of the implications of heritability can seem as though I am keeping my finger in the dike against an inevitable onslaught of scientifically based genetic determinism, the final Plominesque realization that our genes make us who we are, the apotheosis of Galton’s proclamation in 1869: “I propose to show … that a man’s natural abilities are derived by inheritance, under exactly the same limitations as are the form and physical features of the whole organic world” (Hereditary Genius, p. 1).
Robert Plomin, whose name has come up a few times already, is unquestionably the most important psychological geneticist of our time. Trained in social and personality psychology at the University of Texas at Austin in the 1970s (my graduate alma mater, though we didn’t overlap), he went on to faculty positions at the University of Colorado and the Pennsylvania State University (both major American centers for behavior genetics) before moving to London to take a position at the Institute of Psychiatry. Plomin’s career has embodied the integration of behavioral genetics into mainstream social science and psychology. Everywhere Plomin has been, he has initiated twin and adoption studies, many of which continue to make contributions today. Although genetics has always played a central role in Plomin’s research, you would never mistake his work for that of a biologist or quantitative geneticist: he (like me) has always been first and foremost a psychologist.
The Second World War marked a turning point for what was considered acceptable in genetics and its implications for eugenic and racially motivated social policies. To be sure, the change in attitude was not quick or decisive. Tens of thousands of Americans were sterilized involuntarily after the war. Anti-black racism, antisemitism, and anti-immigrant sentiment, needless to say, persisted for a long while and have not yet been eliminated; interracial marriage was still illegal in much of the country during my lifetime. But – and despite the foot-dragging, I think this needs to be recognized as an advance – it slowly became less and less acceptable to adopt openly eugenic or racist opinions in public or to justify them based on science. Retrograde attitudes about such things persist to this day, but they have mostly been relegated to the fringes of scientific discourse.
Many people outside of psychology and biology come to the subject of nature–nurture because of an interest in race. That is unfortunate, but I get it. People, especially in the United States, are obsessed with race, for obvious reasons: American history is indelibly steeped in racial categories. The two foundational failures of the American experience – genocide of Indigenous Americans and enslavement of Africans – happened because of race and racism. Even today in the United States, people of all persuasions think about race all the time, whether as hereditarian racists convinced that there are essential biological differences among ancestral groups, progressives fascinated by personal identity and the degradations that non-white people still experience, or the dozens of racial and ethnic categories obsessively collected by the U.S. census.
This chapter presents how scientists currently use the increasing number of individuals who live to an age above 90 years (i.e. long-lived individuals) to investigate biological determinants of longevity. It will provide an overview of the most extensive studies of exceptionally long-lived individuals and long-living families that have been established since the early 1970s. The focus of the chapter will be on the metabolic phenotypes and the genetic determinants that characterize them. It will discuss the delayed occurrence of age-related disease in long-lived individuals and their offspring as well as their favourable immune-metabolic profile, that is, improved glycaemic control, lipid and thyroid metabolism and immunity. Moreover, it will provide an overview of studies focused on unravelling the genetic component of longevity, which is assumed to be partly responsible for the observed immune-metabolic profile. The findings from these studies indicate that longevity is most likely determined by many different rare protective genetic variants that still need to be identified, for example using whole genome/exome sequencing approaches. Last, but not least, the chapter will discuss some of the implications of the presented findings for medical research on ageing and age-related diseases.
Let’s summarize where the nature–nurture debate stood as the twentieth century drew to a close. When the century began, thinkers were faced for the first time with the hard evolutionary fact that human beings were not fundamentally different biologically than other evolved organisms. Galton and his eugenic followers concluded that even those parts of human experience that seemed to be unique – social, class, and cultural differences; abilities, attitudes, and personal struggles – were likewise subsumed by evolution and the mammalian biology it produced. People and societies could therefore be treated like herds of animals, rated on their superior and inferior qualities, bred to maintain them, treated to fix them, and culled as necessary for the good of the herd. Not every mid-century moral disaster that followed resulted from their misinterpretation of human evolution, but it played a role. Society has been trying to recover from biologically justified racism, eugenics, and genocide ever since.
The theory of evolution, as espoused by Charles Darwin in The Origin of Species in 1859, was difficult to accept for religious believers whose assumptions about the world were shattered by it, but Darwin’s The Descent of Man, published 12 years later, posed even greater challenges to people who did accept it, and those challenges continue today. It has often been noted that a disorienting consequence of the Enlightenment was to force people to recognize that humans were not created at the center of the universe in the image of God, but instead on a remote dust-speck of a planet, in the image of mold, rats, dogs, and chimps. For the entirety of recorded history, moral beliefs about humans had been based on the idea that people were in some fundamental sense apart from the rest of nature. Darwin disabused us of that notion once and for all. The scientific and social upheaval that has occurred since Darwin has been an extended process of coming to terms with a unification of humans and the rest of the natural world.
Phelan-McDermid syndrome is a rare genetic disorder characterised by various neurodevelopmental, medical, and psychiatric issues. Although bipolar disorder-like presentations and catatonia are particularly common, psychosis has also been reported but is less well described. As such, this systematic review sought to characterise the phenomenology of psychosis in Phelan-McDermid syndrome, clarify the association of psychotic symptoms with other neuropsychiatric features of the disorder, and describe antipsychotic treatment response.
Methods:
A literature search was completed in July 2024 using PubMed and Scopus. Only English-language articles that reported the occurrence of psychotic symptoms in Phelan-McDermid syndrome were eligible for inclusion. 18 articles describing 35 individuals were included in the main analyses. Three additional articles of relevance are discussed separately, as they either provided limited clinical information or did not present data in a patient-specific manner.
Results:
The average age of psychosis onset was ∼17 years, and 65% of individuals developed symptoms at or before age 15. ∼69% of individuals also experienced catatonia, ∼81% experienced mood symptoms, and 50% experienced both. Visual hallucinations were the most commonly reported psychotic symptom. Where reported, ∼76% of individuals exhibited at least a partial and/or temporary response to antipsychotic therapy.
Conclusion:
Psychotic presentations in Phelan-McDermid syndrome may qualitatively differ from schizophrenia. Although numerous antipsychotics may be efficacious in the treatment of Phelan-McDermid syndrome-associated psychosis, this review most importantly highlights the paucity of available high-quality evidence to guide treatment decisions in this respect, and as such indicates the need for more reports to be published.
Associations between leptin (LEP) and leptin receptor (LEPR) gene polymorphisms and mood disorders have been found but not yet confirmed in multiple studies. The aim of our study was to study the associations between LEP and LEPR single nucleotide polymorphisms (SNPs) and treatment response of depression. Associations between leptin levels and depression severity were also investigated.
Methods:
The data included 242 depressed patients in secondary psychiatric care. Symptoms of depression were assessed with the Montgomery–Åsberg Depression Rating Scale (MADRS). Previously found LEP and LEPR SNPs associated with depression and other mood disorders were studied. Furthermore, all available LEP and LEPR SNPs were clumped using proxy SNPs to represent gene areas in r2 > 0.2 linkage disequilibrium and their association with treatment response was analysed with logistic regression.
Results:
Two proxy SNPs of LEPR gene, rs12564738 and rs12029311, were associated with MADRS response at 6 weeks (p adjusted = 0.024, p adjusted = 0.024). SNPs from previous studies were not associated with MADRS response, but LEPR rs12145690 from a previous study was strongly associated with rs12564738 (r2 = 0.94). The positive association between leptin levels and MADRS score at baseline after adjusting with age, sex, body mass index (BMI), Alcohol Use Disorders Identification Test score, and smoking was found (p = 0.011).
Conclusion:
Our findings suggest that LEPR polymorphisms are associated with depression treatment response. We also found associations between leptin levels and depression independently of BMI. Further studies and meta-analyses are needed to confirm the significance of found SNPs and the role of leptin in depression.
An important contributor to the decreased life expectancy of individuals with schizophrenia is sudden cardiac death. Arrhythmic disorders may play an important role herein, but the nature of the relationship between schizophrenia and arrhythmia is unclear.
Aims
To assess shared genetic liability and potential causal effects between schizophrenia and arrhythmic disorders and electrocardiogram (ECG) traits.
Method
We leveraged summary-level data of large-scale genome-wide association studies of schizophrenia (53 386 cases, 77 258 controls), arrhythmic disorders (atrial fibrillation, 55 114 cases, 482 295 controls; Brugada syndrome, 2820 cases, 10 001 controls) and ECG traits (heart rate (variability), PR interval, QT interval, JT interval and QRS duration, n = 46 952–293 051). We examined shared genetic liability by assessing global and local genetic correlations and conducting functional annotation. Bidirectional causal relations between schizophrenia and arrhythmic disorders and ECG traits were explored using Mendelian randomisation.
Results
There was no evidence for global genetic correlation, except between schizophrenia and Brugada syndrome (rg = 0.14, 95% CIs = 0.06–0.22, P = 4.0E−04). In contrast, strong positive and negative local correlations between schizophrenia and all cardiac traits were found across the genome. In the most strongly associated regions, genes related to immune and viral response mechanisms were overrepresented. Mendelian randomisation indicated that liability to schizophrenia causally increases Brugada syndrome risk (beta = 0.14, CIs = 0.03–0.25, P = 0.009) and heart rate during activity (beta = 0.25, CIs = 0.05–0.45, P = 0.015).
Conclusions
Despite little evidence for global genetic correlation, specific genomic regions and biological pathways emerged that are important for both schizophrenia and arrhythmia. The putative causal effect of liability to schizophrenia on Brugada syndrome warrants increased cardiac monitoring and early medical intervention in people with schizophrenia.