FMST 210 Week 3 PDF

Week 3: Genetics, Growth, and Health Family Context of Human Development FMST 210 (102) Dr. Rafael Wainer These PowerPoint slides are the exclusive copyright of Professor Wain...

Week 3: Genetics, Growth, and Health Family Context of Human Development FMST 210 (102) Dr. Rafael Wainer These PowerPoint slides are the exclusive copyright of Professor Wainer and may only be used by students enrolled in FMST 210 at the University of British Columbia. Unauthorized or commercial use of these lectures, including uploading to sites off of the University of British Columbia servers, is expressly prohibited. Have you ever thought why do I have this specific eye color? How do you think biology and genetics affect child development? How much should children know/learn/be aware of biological changes leading to puberty and teenagehood? For example, how much did you learn about menstruation in school? If it is an unfolding of a pre-programmed biological plan, why do you think it is still a taboo issue? Genetic Bases of Child Development What are chromosomes and 1 - Mechanisms of genes? Heredity What are dominant and recessive traits? How are 2 - Heredity, they inherited? Environment, and What disorders are Development inherited? Which are caused by too many or too few chromosomes?  Human Genome Research: Hope or Hype? July 2000 Q: How much does genetics play a role in who we are? A: Lots. But not everything can be explained by genetic factors. Copyright © 2019 Pearson Canada Inc. 6  Mechanisms of Heredity The Biology of Heredity Single Gene Influence (Mendelian diseases) Genetic Disorders (non- Mendelian, complex diseases) Many elements of our personality are genetically based but hard to determine  Mendelian Inheritance Discrete factors—genes—that are passed along from generation to generation according to the rules of probability  The Biology of Heredity 1. Gametes (sperm/egg cells) have 23 chromosomes each 2. When combined, they provide 23 pairs of chromosomes  “ ” “ ” Not always is XX or XY (XXY, XYY, XXYY, XXXY, and other combinations)  The Biology of Heredity 1. Each chromosome is made up of DNA (deoxyribonucleic acid and protein) 2. Genes are sections of the DNA strands 3. Genotype = complete set of genes 4. Phenotype = physical, behavioural, and psychological features [genes environment]  Environment Environment Environment Environment Genetics è ç Epigenetics Genotype Phenotype Environment Environment Environment Environment Over the life course of individuals, the contents of human cells mutually interact and are influenced by micro-environments—intra and extra-cellular—and by macro-environments external to the body.  b B recessive dominant  Single Gene Inheritance 1. Gene è Alleles è homozygous (the same, BB) or 2. Gene è Alleles è heterozygous (different, Bb) i. Dominant allele (B): a. Its chemical instructions are followed ii. Recessive allele (b): a. Its chemical instructions are ignored (unless both alleles are recessive, bb) iii. Incomplete dominance: a. One allele doesn’t dominate the other completely Sickle Cell Trait: An Example of Incomplete Dominance  Genetic Disorders 1. Many disorders are homozygous recessive 2. Cystic fibrosis, PKU, albinism, and Tay-Sachs disease 3. Most inherited disorders are very rare (low pop. frequency) 4. Some disorders are sex-linked (e.g. hemophilia) 5. Many children/adults with genetic disorders will experience a normal life.  Genetic Disorders 1. Too many, too few, altered, or damaged chromosomes 2. Down Syndrome = extra 21st chromosome 3. A number of disorders (e.g. Turner’s syndrome; Klinefelter’s syndrome 48, XXYY; XYY complement, XXX syndrome) are caused by missing or extra sex chromosomes 4. Some people are born intersex and never know about it until they do genetic testing or some may never know Pedigree chart showing an inheritance pattern consistent with autosomal dominant transmission.  2. Heredity, Environment, and Development Behavioural What methods do scientists use to study Genetics the impact of heredity Paths from Genes and environment on children’s development? to Behaviour How do heredity and environment work together to influence child development?  Behavioral Genetics 1. The branch of genetics that deals with the inheritance of behavioural and psychological traits 2. Many behavioural genotypes reflect polygenic inheritance, which involves many genes (the effects of these genes are often infinitesimally small) How do genes and the environment work in tandem to influence child development? Epigenetics Study of http://commonfund.nih.gov/epigenomics/figure.aspx heritable phenotype changes that do not involve alterations in the DNA sequence  Behavioral Genetics Twin studies*: 1. clues about the influence of heredity (vs. environment) 2. Monozygotic twins => one fertilized egg 3. Dizygotic twins => two separate eggs fertilized by two separate sperm 4. If monozygotic twins ≈ more alike (than dizygotic twins) => heredity is implicated (*Eugenics history during Nazi Germany of twin experiments) It is clear from multiple lines of evidence that all researched behavioural traits and disorders are influenced by genes (they are heritable). The single largest source of evidence comes from twin studies, where it is routinely observed that monozygotic (identical) twins are more similar to one another than are same-sex dizygotic (fraternal) twins Adoption studies: 1. influence of environment (vs. heredity) a. child’s behavior ≈ the biological parents => impact of heredity b. child’s behavior ≈ the adoptive parents => influence of the environment Developmental psychology – Epigenetics: psychological development as the result of: a. ongoing, b. bi-directional c. heredity environment  Behavioural Genetics 10 most well-replicated findings from behavioral genetics research (Plomin R, DeFries JC, Knopik VS, Neiderhiser JM (January 2016). 1. "All psychological traits show significant and substantial genetic influence." 2. "No traits are 100% heritable." 3. "Heritability is caused by many genes of small effect." 4. "Phenotypic correlations between psychological traits show significant and substantial genetic mediation." 5. "The heritability of intelligence increases throughout development." 6. "Age-to-age stability is mainly due to genetics." 7. "Most measures of the 'environment' show significant genetic influence." 8. "Most associations between environmental measures and psychological traits are significantly mediated genetically." 9. "Most environmental effects are not shared by children growing up in the same family." 10. "Abnormal is normal." Research shows genetic influence in many psychological areas: 1. personality, 2. mental ability/capabilities, 3. mental disorders (difference?), 4. attitudes, and 5. interests In your own childhood, how many of these factors do you think were influenced by genetics?  Paths from Genes to Behaviour The behavioural consequences of genetic instructions depend on the environment in which those instructions develop: Reaction range: the same genotype can produce a range of phenotypes in reaction to environment Why?  Paths from Genes to Behaviour Heredity & environment interact dynamically throughout development 1. Epigenesis Genes are expressed by being transcribed into RNA, and this transcript may then be 2. Methylation translated into protein.  Paths from Genes to Behaviour Correlations from twin and adoption studies to calculate: Heritability coefficients estimate the extent to which differences between people reflect heredity.  Paths from Genes to Behaviour Genes can influence the kind of environment to which a child is exposed 1. Niche-picking 2. Why do you think we often choose people that look alike?  Paths from Genes to Behaviour Counter-intuitively, environmental influences tend to make children within a family different: How? 1. Parents/caregivers don’t provide exactly the same environments for all of their children 2. Parents/caregivers provide the child’s genes and environment, but children also influence their own environments 3. Children come at different moments in life cycle of parents/caregivers and families  The so-called “Sex-Ed Debate” in Ontario (2015/2018/2019) Search in your search engine: “Ontario Sex-Ed Curriculum controversy” This is about getting timely access to physical, mental, emotional, sexual health, and body literacy within the education system.  Brief History: Ontario Sex-Education Curriculum 1998: Sex-Ed Curriculum (pre-Internet) 2010: Updates to curriculum 2015: (Liberal Party) New Curriculum 2018: (Conservative) Scrapped 2015 Curriculum (for one year) (Teachers had to use 1998 Curriculum) 2019: Health and Physical Education (~to Liberal 2015’s Curriculum) From ETFO website: The 1998 curriculum: 1. Before the Internet and social media (e.g. cyberbullying or sexting as everyday issues). 2. Pre-dates legal same-sex marriage and the addition of gender identity and expression to the Ontario Human Rights Code. 3. Elementary students need language to communicate about their bodies and inappropriate sexual touching or abuse. 4. Older students struggle with consent. 5. Reverting back to the 1998 curriculum put children at risk “Having language to name our body parts, being empowered to understand consent and healthy relationships, and being able to address issues such as sexism and homophobia helps kids navigate their social worlds and in some cases, saves their lives.” (ETFO) How would this policy affect children development in the future? 2019: (Conservative) Gov. reintroduced Health and Physical Education Curriculum (similar to 2015 Curriculum)  2019 – New Curriculum Grade 1: students will be taught to identify body parts (incl. genitalia) students will be taught to use body-positive language students will learn about habits and behaviour, including vaping Grade 3: students will learn about the different types of legal and illegal substance use Grade 5: students will learn to identify the factors that affect the development of a person’s self-concept, including their sexual orientation students will learn about the negative effects of making homophobic comments Grade 8: students will learn about gender identity (male, female, Two-Spirit, transgender) and learn more about sexual orientation (heterosexual, gay, lesbian, bisexual, pansexual, asexual) Under the former Liberal government’s plan, gender identity and sexual orientation was to be taught in Grade 6. It has been delayed until Grade 8 students will learn about abstinence, contraception and the use of suitable protection to prevent pregnancy and sexually transmitted blood borne infections (STBBIs) Parents can now opt their child out of sex-ed lessons with a new policy put into place – this must be completed by Nov. 30 The new curriculum has a stronger and earlier emphasis on mental health, starting in Kindergarten  Group activity rules: 1. Randomly assigned by alphabetic order 2. Same group throughout the term 3. Introduce yourselves on the first meeting. 4. Rotate turns (recorder & moderator). 5. Answer as a free-flow thought process. 6. Points are only get if you come to the group activity. 7. Respect for others, talk and listen to create mutual understanding. 8. Work for 45’ (you cannot leave before 10:45). (Use the time to have some small social interactions!).