1. Genetic simplex modeling of personality in adolescent Australian twins N.A. GILLESPIE 1, D. M. EVANS 1, N.G. MARTIN 1 1 Queensland Institute of Medical Research and University of Queensland, Joint Genetics Program, Brisbane, Australia. Supported by Queensland Cancer Fund, Cooperative Research Centre for Discovery of Genes for Common Human Diseases, and NHMRC grants 901061 & 9050998.

2. Modeling personality change Eaves, Eysenck & Martin (1989) Adult personality - High of genetic continuity over time ! Effect stronger in Neuroticism vs Extraversion Genetic continuity in adolescents? Simplex modeling (Boomsma, 1989)

3. Genetic Simplex modeling Autoregressive model Structural equation model η i = β i η i-1 + ζ i var (η i ) = β i 2 var (η i-1 ) + var (ζ i ) ζ i-1  i-1 Y i-1 YiYi Y i+1 ζ i ζ i+1 λ i-1 λ i λ i+1 ε i-1 β i β i+1 ii  i+1 ε iε i ε i+1 Measurement model Y i = λ i η i + ε i var (Y i ) = λ i 2 var (η i ) + var (ε i )

4. TWIN 1 TWIN 2

5. Sample Twin Mole and Twin MAPS projects Assess the genetic / environmental etiology of Melanocytic Naevi (common moles) in twins aged 12 & 14 years + Cognition at 16 81 items JEPQ - Psychoticism (P) - Extraversion (E) - Neuroticism (N)- Lie (L)

6. Data Normal weighted by sex and age Structural equation modeling using ML analysis of individual observations performed in Mx Raw continuous data methods Assumptions of mean and variance homogeneity by twin order and zygosity (and necessarily by sex and age)

7. Polychoric test-retest correlations

8. Twin pair polychoric correlations Consistent with a genetic hypothesis ! Univariate & Multivariate results AE best fitting model

9. P12P14P16 ε1ε1 ε2ε2 ε3ε3 ζ A2 ζ A3 111 E1E1 ζ E1 ζ E2 ζ E3 β E2 β E3 E2E2 E3E3 ζ A1 1 11 β A2 β A3 A1A1 A2A2 A3A3 Psychoticism AE Simplex model

10. ζ A2 111 E1E1 ζ E1 ζ E2 ζ E3 β E2 β E3 E2E2 E3E3 ζ A1 1 11 β A2 β A3 A1A1 A2A2 A3A3 Psychoticism Drop genetic innovation @ 16 years P12P14P16 ε1ε1 ε2ε2 ε3ε3

11. ζ A3 111 E1E1 ζ E1 ζ E2 ζ E3 β E2 β E3 E2E2 E3E3 ζ A1 1 11 β A2 β A3 A1A1 A2A2 A3A3 Psychoticism Drop genetic innovation @ 14 years P12P14P16 ε1ε1 ε2ε2 ε3ε3

12. Psychoticism - Best fitting Simplex model ε1ε1. 36.93. 55 1.15 P12 A1A1 E1E1 P14 A2A2 E2E2 P16 A3A3 E3E3 ε1ε1. 36 ε1ε1 ζ A2. 12 ζ A1. 37 ζ A3. 13.70 ζ E1. 15 ζ E2. 06 ζ E3. 05 111 111

13. Extraversion AE Simplex model E12E14E16 ε1ε1 ε2ε2 ε3ε3 ζ A2 ζ A3 111 E1E1 ζ E1 ζ E2 ζ E3 β E2 β E3 E2E2 E3E3 ζ A1 1 11 β A2 β A3 A1A1 A2A2 A3A3

14. Extraversion Drop genetic innovation @ 16 years E12E14E16 ε1ε1 ε2ε2 ε3ε3 ζ A2 111 E1E1 ζ E1 ζ E2 ζ E3 β E2 β E3 E2E2 E3E3 ζ A1 1 11 β A2 β A3 A1A1 A2A2 A3A3

15. Extraversion Drop genetic innovation @ 14 years E12E14E16 ε1ε1 ε2ε2 ε3ε3 ζ A3 111 E1E1 ζ E1 ζ E2 ζ E3 β E2 β E3 E2E2 E3E3 ζ A1 1 11 β A2 β A3 A1A1 A2A2 A3A3

16. Extraversion - Best fitting Simplex model ε1ε1. 23.92. 53.72 E12 A1A1 E1E1 E14 A2A2 E2E2 E16 A3A3 E3E3 ε1ε1. 23 ε1ε1 ζ A2. 12 ζ A1. 38.93 ζ E1. 35 ζ E2. 18 ζ E3. 17 111 111

17. N12N14N16 ε1ε1 ε2ε2 ε3ε3 ζ A2 ζ A3 111 E1E1 ζ E1 ζ E2 ζ E3 β E2 β E3 E2E2 E3E3 ζ A1 1 11 β A2 β A3 A1A1 A2A2 A3A3 Neuroticism AE Simplex model

18. N12N14N16 ε1ε1 ε2ε2 ε3ε3 ζ A2 111 E1E1 ζ E1 ζ E2 ζ E3 β E2 β E3 E2E2 E3E3 ζ A1 1 11 β A2 β A3 A1A1 A2A2 A3A3 Neuroticism Drop genetic innovation @ 16 years

19. N12N14N16 ε1ε1 ε2ε2 ε3ε3 ζ A3 111 E1E1 ζ E1 ζ E2 ζ E3 β E2 β E3 E2E2 E3E3 ζ A1 1 11 β A2 β A3 A1A1 A2A2 A3A3 Neuroticism Drop genetic innovation @ 14 years

20. Neuroticism - Best fitting Simplex model ε1ε1. 22.93. 49.91 N12 A1A1 E1E1 N14 A2A2 E2E2 N16 A3A3 E3E3 ε1ε1. 22 ε1ε1 ζ A2. 11 ζ A1. 36 ζ A3. 11.76 ζ E1. 39 ζ E2. 22 ζ E3. 15 111 111

21. Lie AE Simplex model L12L14L16 ε1ε1 ε2ε2 ε3ε3 ζ A2 ζ A3 111 E1E1 ζ E1 ζ E2 ζ E3 β E2 β E3 E2E2 E3E3 ζ A1 1 11 β A2 β A3 A1A1 A2A2 A3A3

22. Lie Drop genetic innovation @ 16 years ζ A2 111 E1E1 ζ E1 ζ E2 ζ E3 β E2 β E3 E2E2 E3E3 ζ A1 1 11 β A2 β A3 A1A1 A2A2 A3A3 L12L14L16 ε1ε1 ε2ε2 ε3ε3

23. Lie Drop genetic innovation @ 14 years ζ A3 111 E1E1 ζ E1 ζ E2 ζ E3 β E2 β E3 E2E2 E3E3 ζ A1 1 11 β A2 β A3 A1A1 A2A2 A3A3 L12L14L16 ε1ε1 ε2ε2 ε3ε3

24. Lie - Best fitting Simplex model ε1ε1. 24.84. 46.75 L12 A1A1 E1E1 L14 A2A2 E2E2 L16 A3A3 E3E3 ε1ε1. 24 ε1ε1 ζ A2. 10 ζ A1. 45 ζ A3. 15.87 ζ E1. 28 ζ E2. 23 ζ E3. 09 111 111

25. Discussion Uni- and multivariate analyses Small BUT significant genetic innovations @ 12 & 14 years Genes which effect personality traits at all three ages + New genetic innovations Different environments are salient at different ages

26. Limitations Normal weighted data Removes age and sex effects Does not capture  phenotypic variance with age Analyses based on transformed data to remove skewness Equivalent results ! Sex limitation Evidence of general sex limitation for Neuroticism at 16 years

27. Home Simplex model Neuroticism final model