Resolving the paradox of common, harmful, heritable mental disorders: Which evolutionary genetic models work best?
David Bourget (Western Ontario)
David Chalmers (ANU, NYU)
Rafael De Clercq
Jack Alan Reynolds
Learn more about PhilPapers
Behavioral and Brain Sciences 29 (4):385-404 (2006)
Given that natural selection is so powerful at optimizing complex adaptations, why does it seem unable to eliminate genes (susceptibility alleles) that predispose to common, harmful, heritable mental disorders, such as schizophrenia or bipolar disorder? We assess three leading explanations for this apparent paradox from evolutionary genetic theory: (1) ancestral neutrality (susceptibility alleles were not harmful among ancestors), (2) balancing selection (susceptibility alleles sometimes increased fitness), and (3) polygenic mutation-selection balance (mental disorders reflect the inevitable mutational load on the thousands of genes underlying human behavior). The first two explanations are commonly assumed in psychiatric genetics and Darwinian psychiatry, while mutation-selection has often been discounted. All three models can explain persistent genetic variance in some traits under some conditions, but the first two have serious problems in explaining human mental disorders. Ancestral neutrality fails to explain low mental disorder frequencies and requires implausibly small selection coefficients against mental disorders given the data on the reproductive costs and impairment of mental disorders. Balancing selection (including spatio-temporal variation in selection, heterozygote advantage, antagonistic pleiotropy, and frequency-dependent selection) tends to favor environmentally contingent adaptations (which would show no heritability) or high-frequency alleles (which psychiatric genetics would have already found). Only polygenic mutation-selection balance seems consistent with the data on mental disorder prevalence rates, fitness costs, the likely rarity of susceptibility alleles, and the increased risks of mental disorders with brain trauma, inbreeding, and paternal age. This evolutionary genetic framework for mental disorders has wide-ranging implications for psychology, psychiatry, behavior genetics, molecular genetics, and evolutionary approaches to studying human behavior. (Published Online November 9 2006) Key Words: adaptation; behavior genetics; Darwinian psychiatry; evolution; evolutionary genetics; evolutionary psychology; mental disorders; mutation-selection balance; psychiatric genetics; quantitative trait loci (QTL).
|Keywords||adaptation behavior genetics Darwinian psychiatry evolution evolutionary genetics evolutionary psychology mental disorders mutation-selection balance psychiatric genetics quantitative trait loci (QTL)|
|Categories||categorize this paper)|
Setup an account with your affiliations in order to access resources via your University's proxy server
Configure custom proxy (use this if your affiliation does not provide a proxy)
|Through your library|
References found in this work BETA
No references found.
Citations of this work BETA
Andreas De Block & Bart Du Laing (2007). Paving the Way for an Evolutionary Social Constructivism. Biological Theory 2 (4):337-348.
Robin Brown (2009). Dominic Murphy Psychiatry in the Scientific Image. British Journal for the Philosophy of Science 60 (3):673-678.
Bernard Crespi & Christopher Badcock (2008). The Evolutionary Social Brain: From Genes to Psychiatric Conditions. Behavioral and Brain Sciences 31 (3):284-320.
P. R. Adriaens & A. De Block (2013). Why We Essentialize Mental Disorders. Journal of Medicine and Philosophy 38 (2):107-127.
Matthew C. Keller (2008). Problems with the Imprinting Hypothesis of Schizophrenia and Autism. Behavioral and Brain Sciences 31 (3):273-274.
Similar books and articles
Tom Campbell, Daria Osipova & Seppo Kähkönen (2006). Finland's Galapagos: Founder Effect, Drift, and Isolation in the Inheritance of Susceptibility Alleles. Behavioral and Brain Sciences 29 (4):409-410.
Matthew C. Keller (2004). Evolutionary Theories of Schizophrenia Must Ultimately Explain the Genes That Predispose to It. Behavioral and Brain Sciences 27 (6):861-862.
Pieter R. Adriaens & Andreas de Block (eds.) (2011). Maladapting Minds: Philosophy, Psychiatry, and Evolutionary Theory. Oxford University Press.
Jerome C. Wakefield (2006). High Mental Disorder Rates Are Based on Invalid Measures: Questions About the Claimed Ubiquity of Mutation-Induced Dysfunction. Behavioral and Brain Sciences 29 (4):424-426.
Martin Brüne (2006). Evolutionary Psychiatry is Dead – Long Liveth Evolutionary Psychopathology. Behavioral and Brain Sciences 29 (4):408-408.
Nicholas B. Allen & Paul B. T. Badcock (2006). Genes for Susceptibility to Mental Disorder Are Not Mental Disorder: Clarifying the Target of Evolutionary Analysis and the Role of the Environment. Behavioral and Brain Sciences 29 (4):405-406.
David C. Airey & Richard C. Shelton (2006). Praise for a Critical Perspective. Behavioral and Brain Sciences 29 (4):405-405.
Martin Voracek (2006). Population Genetical Musings on Suicidal Behavior as a Common, Harmful, Heritable Mental Disorder. Behavioral and Brain Sciences 29 (4):423-424.
Oliver Mayo & Carolyn Leach (2006). Are Common, Harmful, Heritable Mental Disorders Common Relative to Other Such Non-Mental Disorders, and Does Their Frequency Require a Special Explanation? Behavioral and Brain Sciences 29 (4):415-416.
Matthew C. Keller & Geoffrey Miller (2006). An Evolutionary Framework for Mental Disorders: Integrating Adaptationist and Evolutionary Genetic Models. Behavioral and Brain Sciences 29 (4):429-441.
Added to index2009-01-28
Total downloads42 ( #37,853 of 1,096,411 )
Recent downloads (6 months)6 ( #33,652 of 1,096,411 )
How can I increase my downloads?