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Genetics, Families, & Social Development: The Important Contributions of Adoptive Families Half-Day Conference for Adoptive Families and Professionals Spence-Chapin New York April 18, 2008. Jenae Neiderhiser, Ph.D. The Pennsylvania State University Leslie Leve, Ph.D.
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Genetics, Families, & Social Development: The Important Contributions of Adoptive Families Half-Day Conference for Adoptive Families and Professionals Spence-Chapin New York April 18, 2008 Jenae Neiderhiser, Ph.D. The Pennsylvania State University Leslie Leve, Ph.D. Oregon Social Learning Center
Workshop Outline • Overview of Genetics • Description of the Early Growth & Development Study (and family of studies) • Early Results from EGDS • Implications for Prevention and Services for Adoptive Families
I. Overview of Genetics Developmental Behavior Genetics Behavior genetics: Exploration of the potential influence of genes and experience upon a behavior Focus: Individual differences & the similarity (covariance) of relatives Research Strategies: Twin studies, Family studies, & Adoption studies (and combinations)
Individual Differences: Concerned with differences among individuals within a population e.g. How does antisocial behavior differ in a population of teenagers? Group Differences: Concerned with differences between groups within a population e.g. How do teenage boys and girls differ for antisocial behavior?
Estimating genetic & environmental influences • Examine family members who differ in degree of genetic relatedness • identical twins, fraternal twins, parent-biological child, adoptive parent-adopted child • Compare similarity in family members (correlations)
Genetic influences • Indicated by increased similarity for increased genetic relatedness • MZ twins > DZ twins > adopted siblings • Shared environmental influences • Indicated by within-family similarity • ANY similarity in adopted siblings or between adopted children & their adoptive parents • Nonshared environmental influences • Indicated by differences in family members • ANY differences between MZ twins
Heritability: Proportion of total variance that can be explained by genetic differences in individuals in that population Environmentality: Proportion of total variance that can be explained by nongenetic (environmental) differences in individuals in that population Shared environment – all nongenetic influences that make family members similar to one another Nonshared environment – all nongenetic influences that make family members different from one another
Important Points about genetic and environmental influences Heritability does notequal immutability – it can be changed and modified by the environment Heritability can, and does, change over time There is a large amount of variation that is not due to genetic factors
“Genetic influence” on a phenotype does not imply: -the environment is unimportant -genetic determinism, or even a close relationship between genes & behavior Environmental influences are all nongenetic influences that contribute to individual differences May include: prenatal effects, environmental influences on DNA, traditional environmental factors (parenting, neighborhood, SES, etc.)
Patterns of Genetic & Environmental Influences Wide range of behaviors have been examined across the lifespan • Physical characteristics (height/weight) • Personality & temperament • Mental health & psychopathology • Social relationships & behavior
Genetic and Environmental Influences on Psychological Traits
Genetic and Environmental Influences on Interpersonal Relationships
General patterns of genetic & environmental influences on interpersonal relationships most salient for children & adolescents Parenting • Warmth/Support & Conflict/Negativity • Tend to show genetic influences • Monitoring & Control • Tend to show shared environmental influences Sibling relationships • Mostly reciprocal in nature due to shared environmental influences Peer relationships • Vary by construct, generally due to genetic & shared environmental influences
How can we understand genetic influences on “environmental” measures and interpersonal relationships? GP Parent Temperament .50 Gc Parenting Behavior and/or Parent-Child Relationship Passive Genotype-Environment Correlation
How can we understand genetic influences on “environmental” measures and interpersonal relationships? parent influences Child behavioral CHARACTERISTICS Parental CONFLICT/NEG child evokes FAMILY EFFECTS CHILD EFFECTS GC Evocative Genotype-Environment Correlations
Why do we care? Direction of effects: Child to parent (evocative rGE) Parent to child (passive rGE or E) What are the mechanisms of the environment’s influence on child outcomes?
Mechanisms of Parenting Gp Gc Passive GE Correlation Contextual factors Evocative GE Correlation Parent’s characteristics Parenting behavior Child’s characteristics
Nonshared Environment in Adolescent Development Project (NEAD) Reiss, Hetherington, Plomin (PIs of T1 & T2), Neiderhiser (PI T3) Time 2 Assessment N=384 families Age range 13-21 2 family types: nondivorced & step families 5 sibling types: MZ & DZ twins, full, half, step
Twin/Offspring Study in Sweden • 909 pairs of twin families • 350 pairs of twin fathers (128 MZ; 183 DZ) • 559 pairs of twin mothers (254 MZ; 285 DZ) • 1 adolescent child/family (11-22 yrs) • Cousin pairs w/in 4 years of age • Same sex cousin pairs (49% boys) • Spouse/other parent • Cohabitating for at least 5 years • Over 90% of spouses are biological parent of child
Child of Twin 2 NEAD and TOSS Designs TOSS NEAD 1.0=MZ twin parents; .50=DZ twin parents Dad Mom Twin Parent 2 Twin Parent 1 Spouse 2 Spouse 1 Child 1 Child 2 Child of Twin 1 1.0=MZ twins; .50=DZ twins & full siblings; .25=half siblings; 0=step siblings .25=children of MZ twin parents; .125=children of DZ twin parents
Parenting: GE Correlation Passive & Evocative GE Correlation Mothering Passive & Evocative GE Correlation Mostly Evocative GE Correlation Fathering Evocative & Passive GE Correlation
Evidence for Evocative GE Correlation: Adopted Adolescents and Adoptive Parents Adoptive Parents Adoptive Mother Marital Warmth Mother’s Discipline -.46* -.05 .48* .44* Psychiatric Disorders Antisocial/ Hostile Beh. .31* Birth Parents Adopted Child from Ge et al., 1996
Average negative control by adoptive parents of children whose birth mothers were antisocial (at risk) or not Age (in years) from O’Connor et al., 1998
Gene-environment Interplay • Two types • Genotype – environment correlation • Genotype x environment interaction • Genotype x environment interaction • BOTH genetic factors & environmental factors (typically risk) are required for a specific outcome • For example…
Interaction of genetic influence and family characteristics in childhood aggression (Cadoret, 1995) Antisocial personality in birth parent Number of childhood aggression symptoms No antisocial personality in birth parent Unfavorable Favorable Adverse Adoptive Home Environment Factors (adoptive parent marital or legal problems or psychiatric d/o)
NEAD Robert Plomin (IoP) David Reiss (GWU) E. Mavis Hetherington (UVA) Mark Feinberg (PSU) Erica Spotts (NIA) Dean Hamer (NCI) Jody Ganiban (GWU) Rich Rende (Brown) many other students & postdocs R01s MH43373, MH48825, & MH59014 & the William T. Grant Foundation TOSS Paul Lichtenstein (KI) David Reiss (GWU) Nancy Pedersen (KI) Jody Ganiban (GWU) Erica Spotts (NIA) Suzanne Haddad (GWU) Jurgita Naruyste (KI) Jennifer Ulbricht (GWU) Lennart Martinnson (KI) Elias Ericksson (Göteborgs Universitet) R01MH54601 & Riksbankens Jubieleumsfond (DNA collection & genotyping) Thanks to the research teams that make this work possible
II. Early Growth and Development Study • 560 domestic adoption placements to non-relative families (360 in EGDS-Toddler and 200 in EGDS-Phase 2) • Adoption occurred within 3 mo. post-partum • Infant free of major medical problems • 3 major assessments for birth parents and 6 major assessments for adoptive families spanning infancy through 1st grade (EGDS-School) • Multimethod, multiagent approach
Early Growth and Development Study • 9 mo, 18 mo & 27 mo in-person assessment of adoptive families • 3-6 mo & 18 mo in-person assessment for birth parents • Multimethod, multiagent approach
BM AM BF AF AC EGDS study design • Yoked Adoption Unit: • Birth mother/birth father, adoptive mother/father, & adopted child
EGDS Family of Studies EGDS-Toddler (PI: Reiss) Sept 2002- Aug 2007 n = 360 yoked adoption units parenting, context, externalizing, internalizing, social competence, birth parent characteristics 3 mo to 6 mo 36- 48 mo 4 ½ yrs Prenatal Period 9 mo 18 mo 27 mo 6 yrs 7 yrs EGDS-School (PI: Leve) Sept 2007 – July 2012 n = 360 New: Emergent literacy, executive functioning, HPA axis functioning EGDS-Phase 2 (PI: Neiderhiser) Sept 2007 – May 2012 n = 200 NEW + 360 from EGDS-Toddler New: 200 cases, DNA, enhanced measurement of birthparent experiences, prenatal exposures
Recruitment locations • Three data collection sites • Pacific Northwest (Oregon Social Learning Center) • Mid-Atlantic (George Washington University) • Southwest (University of California, Davis) • One new site added for EGDS-Phase 2 • Midwest (University of Minnesota) • (and PI moved to Penn State)
Recruitment Strategy • Agency Recruitment • Each data collection site identifies “local” agencies • Collects data on number and type of placements • Identify agency liaison once agency agrees to participate • 33 agencies in 10 states participated in EGDS-toddlers • 16 agencies participating in EGDS-Phase 2 (13 from EGDS-toddlers, 3 new)
Recruitment Strategy • Strategy to maximize linked birth parents & adoptive parents • Adoptive family recruitment • Eligible adoptive families are mailed a letter by agency • Includes postage paid postcard to decline contact • If no postcard received within 2 weeks of mailing birth mother contact information is requested • If birth mother agrees to participate study recruiter contacts adoptive family • First assessment – 6 mo telephone interview
Recruitment Strategy • Birth mother recruitment • If no postcard received within 2 weeks of mailing birth mother contact information is requested • Birth mother is contacted by study recruiter • First assessment – Wave 1 in-person interview, 3-6 months postpartum • EGDS Toddlers/School – 360 yoked birth mothers, 517 total (many unyoked)
Recruitment Strategy • Birth father recruitment • Contact information requested from agency after birth mother and adoptive family agree to participate • Birth mothers are asked for contact information if agency can not provide this • Birth fathers are critical for the study (provide 50% of child’s genes) • EGDS Toddlers/School – 105 yoked birth fathers, 147 total (some unyoked)
EGDS constructs • Birth parents, adoptive parents, and children • Externalizing, internalizing, social competence • Alcohol & drug use and problems • Temperament • Social context (stress, social support, economic circumstances, partner/marital relations) • Executive functioning and literacy • DNA and salivary cortisol samples • Adoptive parents only • Parenting • Birth parents only • Prenatal exposure to substances, toxins, stress
Assessment • Telephone Assessments (10-15 minutes) • General well-being, short questionnaires • Mailed/Web-Based Interviews (1-1.5 hrs) • Completed before in-person assessments • Cortisol collection mailed after in-person visit • In-person Assessments (2-3 hours) • In home or convenient other location • Computer-administered questions & interview • Video-recorded child tasks, parent-child interactions and marital interactions • DNA collection
Barrier Task – designed to elicit frustration (9 mo – Wave 1)
Clean-up Task – designed to see how parent structures task & child compliance • 18-month old task (Wave 2) • Show video
Flower Print Task – designed to examine coparenting (9 mo – Wave 1)
Demographics (Con’t) • Adoptive Parents • 1% single • 84% AM, 86% AF married • 1% divorced/separated • 9% remarried • 5% AM, 4% AF cohabitating, committed rel. • Birth Parents • 77% BM, 72% BF single • 8% BM, 22% BF married • 14% BM, 5% BF divorced/separated • 1% BM & BF remarried
EGDS-Phase 2 (PI: Neiderhiser, R01 DA020585) Objectives: • (1) Collection of DNA from all members of yoked adoption unit • Birth parents • Adopted child • Adoptive parents • (2) Addition of 200 more yoked adoption units
EGDS-School: Family Process, Genes, and School Entry (PI: Leve, R01 HD42608-06) • Objectives: • Examine GxE mechanisms in preschool, school entry, and 1st grade • 2) Examine hypothesized social and neuroregulatory mechanisms specific to this developmental period: emergent literacy, HPA axis functioning, & executive functioning
Future Directions • Emotion regulation within the family • Applying for a grant to code the video taped data • Emotion regulation within dyads • Coparenting • Translate interviews • Allow recruitment of a Spanish-speaking population • Capture changing trends in adoption