Angelica Ronald


Professor of Psychology and Genetics and Director of the GEL lab

Centre for Brain and Cognitive Development, Department of Psychological Sciences, Birkbeck, University of London WC1E 7XH.


Tel: 020 7631 6342


Research interests

Quantitative genetics; Molecular genetics; Child and adolescent psychopathology; Autistic spectrum disorders, Attention deficit hyperactivity disorder (ADHD), Psychosis; Comorbidity; Genetic and Environmental risk factors across development.

Curriculum vitae

Angelica Ronald is Professor of Psychology and Genetics at the Centre for Brain and Cognitive Development, Birkbeck, University of London, where she co-directs the Genes Environment Lifespan laboratory and the BRIDGE wet lab. She gained postdoctoral training in molecular genetics funded by an Autism Speaks fellowship and a PhD in Quantitative Genetics from King’s College London. Prior to that she received her BA from the University of Oxford in Experimental Psychology.  Professor Ronald has 19 years' experience of large-scale research with a focus on genetic and environmental causes of neurodevelopment and mental health in children and adolescence. Her research includes the first study to show high genetic overlap between autism and ADHD in childhood, and the first genome-wide association study of specific psychotic experiences in adolescence. Her recent research has included large-scale meta-genome-wide association analyses of cohorts such as TEDS, ALSPAC and CATSS. She is co-I of Babytwins, a 5-year study of infant twins assessed on an extensive neurocognitive battery.  Her research prizes include the Association for Psychological Sciences Janet Taylor Spence award and the British Psychological Society Spearman medal. Prof Ronald has >130 publications, is a Fellow of the Association for Psychological Science and is editor of the Journal of Child Psychology and Psychiatry, ranked top in the field of developmental psychology (ISI, 2017). She co-founded the London Genetics Network, a new hub funded by the Genetics Society involving over 30 institutions and 300 members. The network aims to increase collaboration, support for early career researchers and skill sharing in human genetic research in and around London.  




In Press

Gidziela, A., Ahmadzadeh, Y.I., Michelini, G., Allegrini, A.G., Agnew-Blais, J., Lau, L.Y., Duret, M., Procopio, F., Daly, E., Ronald, A., Rimfeld, K. & Malanchini, M.  (In press). A meta-analysis of genetic effects on neurodevelopmental disorders and co-occurring conditions. Nature Human Behaviour

Hannigan, L., Askeland, R.B., Ask, H., Tesli, M., Corfield, E., Ayorech, Z., Magnus, P., Njølstad, P.R., Øyen, A-S, Stoltenberg, C., Andreassen, O.A., Ronald, A., Davey Smith, G., Reichborn-Kjennerud, T. & Havdahl., A. (in press). Developmental milestones in early childhood and genetic liability to neurodevelopmental disorders. Psychological Medicine.

Gidziela, A., Malanchini, M., Rimfeld, K., McMillan, A., Ronald, A., Viding, E., Pike, A., Asbury, K., Eley, T. C., von Stumm, S., & Plomin, R. (In press). Explaining the influence of nonshared environment (NSE) on symptoms of behaviour problems from preschool to adulthood: Mind the missing NSE gap. Journal of Child Psychology and Psychiatry.

Viktorsson, C., Portugal, A.M., Li, D., Rudling, M., Siqueiros Sanchez, M., Tammimies, K., Taylor, M.J., Ronald, A. & Falck-Ytter, T., (in press). Preferential looking to eyes versus mouth in early infancy: Heritability and link to concurrent and later development, Journal of Child Psychology and Psychiatry.

Havers, L., von Stumm, S., Cardno, A.G., Freeman, D. & Ronald, A. (in press). Psychotic experiences and negative symptoms from adolescence to emerging adulthood: developmental trajectories and associations with polygenic scores and childhood characteristics. Psychological Medicine

Taylor, M. J., Ronald, A., Martin, J., Lundström, S., Hosang, G. M. & Lichtenstein, P. (in press). Examining the association between childhood autistic traits and adolescent hypomania: a longitudinal twin study. Psychological Medicine.



Viktorsson, C., Lindskog, M., Li, D., Tammimies, K., Taylor, M.J.,  Ronald, A. and Falck-Ytter, T. (2022) Infants’ sense of approximate numerosity: Heritability and link to other concurrent traits. Developmental Science.

Austerberry, C., Mateen, M., Fearon, P.* & Ronald, A.* (2022). Heritability of Psychological Traits and Developmental Milestones in Infancy: A Systematic Review and Meta-Analysis of Twin Studies. JAMA Network Open, 5(8):e2227887. *equal contributors

Ronald, A. & Pain, O. (2022). A revolution is brewing in how we understand the shared genetic causes of psychiatric disorders. American Journal of Psychiatry, 179, 791-3.

Austerberry, C., Fearon, P., Ronald, A., Leve, L.D., Ganiban, J.M., Natsuaki, M.N., Shaw, D.S., Neiderhiser, J.M. & Reiss, D. (2022) Early manifestations of intellectual performance: evidence that genetic effects on later academic test performance are mediated through verbal ability in early childhood. Child Development, 93, e188-e206.

Ronald, A. (2022). Transdiagnostic research: Transitory or transformative? Journal of Child Psychology and Psychiatry, 63, 721-723.

Gidziela, A., Rimfeld, K., Malanchini, M., Allegrini, A.G., McMillan, A., Selzam, S., Ronald, A., Viding, E., von Stumm, S., Eley, T.C. & Plomin, R. (2022). Using DNA to predict behaviour problems from preschool to adulthood. Journal of Child Psychology and Psychiatry, 63, 781-792.

Capp, S.J., Agnew-Blais, J., Lau-Zhu, A. , Colvert, E., Tye, C., Aydin, Ü., Lautarescu, A., Ellis, C., Saunders, T., O'Brien, L., Ronald, A., Happé, F., McLoughlin, G. (2022). Is quality of life related to high autistic traits, high ADHD traits and their Interaction? Evidence from a Young-Adult Community-Based twin sample. Journal of Autism and Developmental Disorders. doi: 10.1007/s10803-022-05640-w

Portugal, A.M., Taylor, M.J., Viktorsson, C., Nyström, P., Li, D., Tammimies, K., Ronald, A., & Falck-Ytter, T., (2022). Pupil size and pupillary light reflex in early infancy: heritability and link to genetic liability to schizophrenia. Journal of Child Psychology and Psychiatry, 63, 1068-1077.

Taylor, M.J., Freeman, D., Lundström, S., Larsson, H. & Ronald, A. (2022). Heritability of Psychotic Experiences in Adolescents and Interaction With Environmental Risk. JAMA Psychiatry, 79, 889-897.

Havers, L., Freeman, D., Cardno, A.G., & Ronald, A. (2022). The latent structure of negative symptoms in the general population in adolescence and emerging adulthood. Schizophrenia Bulletin Open, 3, sgac009.

Hosang, G.M., Martin, J., Karlsson, R., Lundström, S., Larsson, H., Ronald, A., Lichtenstein, P. &Taylor, M.J. (2022) Association of aetiological factors for hypomanic symptoms, bipolar disorder and other severe mental illnesses: twin and polygenic risk score analysis. JAMA Psychiatry, 79, 143-150.

Colvert, E, Simonoff, E., Capp, S.J., Ronald, A., Bolton, P. and Happé, F. (2022) Autism Spectrum Disorder and mental health problems: patterns of difficulties and longitudinal trajectories in a population-based twin sample. Journal of Autism and Developmental Disorders, 52, 1077–1091.



Ronald, A., De Bode, N. & Polderman, T.V.C. (2021). Systematic review: How the ADHD polygenic risk score adds to our understanding of ADHD and associated traits. Journal of the American Academy of Child and Adolescent Psychiatry, 60, 1234-1277.

Barkhuizen, W., Dudbridge, F. & Ronald, A. (2021). Genetic overlap and causal associations between smoking behaviours and mental health. Scientific Reports, 11 (14871).

Franke, B., Fombonne, E. & Ronald, A. (2021). The new genetics of autism. Journal of Child Psychology and Psychiatry, 62, 1271-1273.

Falck-Ytter, T., Hamrefors, L., Siqueiros Sanchez, M., Portugal, A.M., Taylor, M. J., Li, D., Viktorsson, C., Hardiansyah, I., Myers, L., Westberg, L., Bolte, S., Tammimies, K., Ronald, A. (2021).  Babytwins Study Sweden (BATSS): A multi-method infant twin study of genetic and environmental factors influencing infant brain and behavioral development. Twin Research and Human Genetics, 24, 217-227.

Gómez-Vallejo, M., Leoni, M., Ronald, A., Colvert, E., Happé, F. & Bolton, P. (2021) Autism spectrum disorder and obstetric optimality: a twin study and meta-analysis of sibling studies. Journal of Child Psychology and Psychiatry, 62, 1353-1362.

Mason, D., Ronald, A., Ambler, A., Caspi, A., Houts, R., Poulton, R., Ramrakha, S., Wertz, J., Moffitt, T.E. & Happé, F. (2021). Autistic traits are associated with faster pace of aging: Evidence from the Dunedin Study at age 45. Molecular Autism, 14, 1684-1694.

Shakoor, S., Zavos, H.M.S., Gregory, A. M. & Ronald, A. (2021). The association between bullying-victimisation and sleep disturbances in adolescence: Evidence from a twin study. Journal of Sleep Research, 30, e13321.

Reed, Z.E., Larsson, H., Haworth, C.M.A., Rai, D., Lundstrom, S., Ronald, A., Reichenberg, A., Lichtenstein, P. & Davis, O.S.P. (2021). Mapping the genetic and environmental aetiology of autistic traits in Sweden and the UK. Journal of Child Psychology and Psychiatry Advances, 1, e12039. 

Sanchez, M.S., Ronald, A., Mason, L., Jones, E.J.H., Bölte, S., Falck-Ytter, T. (2021). Visual disengagement in young infants in relation to age, sex, SES, developmental level and adaptive functioning. Infant Behavior and Development, 63, 101555. 

Cardno, A. G., Selzam, S., Freeman, D. & Ronald, A. (2021). Psychotic-like experiences in adolescence occurring in combination or isolation: associations with schizophrenia risk factors. Psychiatric Research and Clinical Practice, 3, 67-75. 



Hollowell, A. & Ronald, A. (2020). Psychotic experiences associate with a bias against disconfirmatory evidence (BADE) in adolescence. Schizophrenia Research, 218, 304-305.

Ronald, A. (2020). Polygenic scores in child and adolescent psychiatry - strengths, weaknesses, opportunities and threats. Journal of Child Psychology and Psychiatry, 61, 519-521.

Barkhuizen, W., Pain, O., Dudbridge, F. & Ronald, A. (2020). Genetic overlap between psychotic experiences in the community across age and with psychiatric disorders. Translational Psychiatry, 10, 86.

Madrid-Valero, J.J., Ronald, A.Shakeshaft, N., Schofield, K., Malanchini, M. & Gregory, A.M. (2020). Sleep quality, insomnia and internalising difficulties in adolescents: insights from a twin study. Sleep, 43.



Saffari, A., Arno, M., Ronald, A., Wong, C., Schalkwyk, L., Mill, J., Dudbridge, F., & Meaburn. E. L. (2019). RNA sequencing of identical twins discordant for autism reveals blood-based signatures implicating immune and transcriptional dysregulation. Molecular Autism, 10:38. doi: 10.1186/s13229-019-0285-1.

Hosang, G., Lichtenstein, P., Ronald, A., Lundström, S. & Taylor, M. J. (2019) An investigation of the shared genetic and environmental architecture of ADHD and hypomanic symptoms in youths. A longitudinal twin study. JAMA Psychiatry, 76, 1150-1158

Havers, L., Taylor, M. J., & Ronald, A. (2019). Genetic and environmental influences on the stability of psychotic experiences and negative symptoms in adolescence. Journal of Child Psychology and Psychiatry, 60, 784-792.

Ronald, A. (2019). The psychopathology p factor: will it revolutionise the science and practice of child and adolescent psychiatry?  Journal of Child Psychology and Psychiatry, 60, 497-499.

Barkhuizen, W., Taylor, M. J., Freeman, D. & Ronald, A. (2019). A twin study on the association between psychotic experiences and tobacco use during adolescence. Journal of the American Academy of Child and Adolescent Psychiatry, 58, 267-276.



Wallace, G. L., Llewellyn, C., Fildes, A. & Ronald, A. (2018). Autism spectrum disorder and food neophobia: clinical and subclinical links. The American Journal of Clinical Nutrition, 108, 701-707.

Ronald, A. & Pain, O. (2018). A systematic review of genome-wide research on psychotic experiences and negative symptom traits: New revelations and their implications for psychiatry. Human Molecular Genetics, 1;27(R2), R136-R152

Pain, O., Dudbridge, F. & Ronald, A. (2018). Are your covariates under control? How normalization can re-introduce covariate effects. European Journal of Human Genetics, 26, 194-1201.

Shakoor, S., McGuire, P., Cardno, A. G., Freeman, D. & Ronald, A. (2018). A twin study exploring the association between childhood emotional and behaviour problems and specific psychotic experiences in a community sample of adolescents. Journal of Child Psychology & Psychiatry, 59, 565-573.

Pain, O., Dudbridge, F., Cardno, A.G., Freeman, D., Yi, L., Lundstrom, S., Lichtenstein, P. & Ronald, A. (2018). Genome-wide analysis of adolescent psychotic-like experiences shows genetic overlap with psychiatric disorders. Neuropsychiatric Genetics, 177, 416-425.

St Pourcain, B. Robinson, E. R., Anttila, V., Bulik Sullivan, B., Maller, J., Golding, J., Skuse, D., Ring, S., Evans, D. M., Zammit, S., Fisher, S. E., Neale, B. M., Anney, R., Ripke, S., Hollegaard, M. V., Werge, T., iPSYCH-SSI-Broad Autism Group, Ronald, A., Grov, J., Hougaar, D. M., Børglum, A.D., Mortensen, P. B., Daly, M., Davey Smith, G. (2018). ASD and schizophrenia show distinct developmental profiles in common genetic overlap with population-based social-communication difficulties. Molecular Psychiatry, 23, 263–270.



Cheesman, R., Selzam, S., Ronald, A., Dale, P. S., McAdams, T. A., Eley, T. C. & Plomin, R. (2017). Childhood behaviour problems show the greatest gap between DNA-based and twin heritability. Translational Psychiatry, 7(12):1284.

Janecka, M., Haworth, C. M. A., Ronald, A., Krapohl, E., Happé, F., Mill, J., Schalkwyk, L. C., Fernandes, C., Reichenberg, A. & Rijsdijk, F. (2017). Paternal age alters social development in offspring. Journal of the American Academy of Child and Adolescent Psychiatry, 56, 383-390.

Singham, T., Viding, E., Schoeler, T., Arseneault, L., Ronald, A., Cecil, C. M., McCrory, E., Rijsdijk, F., Pingault, J. (2017). Concurrent and longitudinal impact of peer victimisation on mental health: A tale of vulnerability and resilience. JAMA Psychiatry, 74, 1112-1119.

Willfors, C. and Carlsson, T. and Anderlid, B.-M. and Nordgren, A. and Kostrzewa, E. and Berggren, S. and Ronald, Angelica and Kuja-Halkola, R. and Tammimies, K. and Bolte, S. (2017) Medical history of discordant twins and environmental etiologies of autism.Translational Psychiatry 7 , e1014. ISSN 2158-3188.

St Pourcain, B. and Robinson, E. and Anttila, V. and Bulik-Sullivan, B. and Maller, J. and Golding, J. and Skuse, D. and Ring, S. and Evans, D. and Zammit, S. and Fisher, S. and Neale, B. and Anney, R. and Ripke, S. and Hollegaard, M. and Werge, T. and Ronald, Angelica and Grove, J. and Hougaard, D. and Børglum, A. and Mortensen, P. and Daly, M. and Davey Smith, G. (2017) ASD and schizophrenia show distinct developmental profiles in common genetic overlap with population-based social-communication difficulties. Molecular Psychiatry , ISSN 1359-4184. (In Press)

Hosang, G. and Cardno, A.G. and Freeman, D. and Ronald, Angelica (2017) Characterization and structure of hypomania in a British nonclinical adolescent sample. Journal of Affective Disorders 207 , pp. 228-235. ISSN 0165-0327.



Taylor, Mark J. and Freeman, D. and Ronald, Angelica (2016) Dimensional psychotic experiences in adolescence: Evidence from a taxometric study of a community-based sample. Psychiatry Research 241 , pp. 35-42. ISSN 0165-1781.

Micalizzi, L. and Ronald, Angelica and Saudino, K.J. (2016) A genetically informed cross-lagged analysis of autistic-like traits and affective problems in early childhood. Journal of Abnormal Child Psychology 44 (5), pp. 937-947. ISSN 0091-0627.

Taylor, M. and Lichtenstein, P. and Larsson, H. and Ronald, Angelica and Anckarsäter, H. and Greven, C.U. (2016) Is there a female protective effect against ADHD? Evidence from two representative twin samples. Journal of the American Academy of Child and Adolescent Psychiatry 55 (6), 504-512.e2. ISSN 0890-8567.

Robinson, E.B. and St Pourcain, B. and Anttila, V. and Kosmicki, J. and Bulik-­‐Sullivan, B. and Grove, J. and Maller, J. and Samocha, K.E.and Sanders, S. and Ripke, S. and Martin, J. and Hollegaard, M.V. and Werge, T. and Hougaard, D.M. and iPSYCH-­‐SSI-­‐Broad Autism Group, A. and Neale, B.M. and Evans, D.M. and Skuse, D. and Mortensen, P.B. and Børglum, A.D. and Ronald, Angelica and Davey Smith, G. and Daly, M.J. (2016) Genetic risk for autism spectrum disorders and neuropsychiatric variation in the general population.Nature Genetics 48 (5), pp. 552-555. ISSN 1061-4036.

Shakoor, Sania and Zavos, H. and Haworth, C.M.A. and McGuire, P. and Cardno, A.G. and Freeman, D. and Ronald, Angelica (2016)Association between stressful life events and psychotic experiences in adolescence: evidence for gene-environment correlations.British Journal of Psychiatry , ISSN 0007-1250.

Zavos, H.M.S. and Eley, T.E. and McGuire, P. and Plomin, R. and Cardno, A.G. and Freeman, D. and Ronald, Angelica (2016) Shared etiology of psychotic experiences and depressive symptoms in adolescence: a longitudinal twin study. Schizophrenia Bulletin 42 (5), pp. 1197-1206. ISSN 0586-7614.

Tick, B. and Colvert, E. and McEwen, F. and Stewart, C. and Woodhouse, E. and Gillan, N. and Hallett, V. and Lietz, S. and Garnett, T. and Simonoff, E. and Ronald, Angelica and Bolton, P. and Happé, F. and Rijsdijk, F. (2016) Autism Spectrum Disorders and other mental health problems: exploring etiological overlaps and phenotypic causal associations. Journal of the American Academy of Child & Adolescent Psychiatry 55 (2), pp. 106-113. ISSN 0890-8567.

McEwen, F.S. and Stewart, C.S. and Colvert, E. and Woodhouse, E. and Curran, S. and Gillan, N. and Hallett, V. and Lietz, S. and Garnett, T. and Ronald, Angelica and Murphy, D.G.M. and Happé, F. and Bolton, P. (2016) Diagnosing Autism Spectrum Disorder in community settings using the development and well-being assessment: validation in a UK population-based twin sample. Journal of Child Psychology and Psychiatry 57 (2), pp. 161-170. ISSN 0021-9630.

Pinto, R. and Rijsdijk, F. and Ronald, Angelica and Asherson, P. and Kuntsi, J. (2016) The genetic overlap of Attention-Deficit/Hyperactivity Disorder and Autistic-like traits: an investigation of individual symptom scales and cognitive markers. Journal of Abnormal Child Psychology 44 (2), pp. 335-345. ISSN 0091-0627.

Thomas, Michael S.C. and Forrester, N.A. and Ronald, Angelica (2016) Multi-scale modeling of gene-behavior associations in an artificial neural network model of cognitive development. Cognitive Science 40 (1), pp. 51-99. ISSN 1551-6709.


Jones, A. and O’Nions, E. and Tick, B. and Rijsdijk, F. and Happé, F. and Plomin, R. and Ronald, Angelica and Viding, E. (2015) Examining the genetic and environmental associations between autistic social and communication deficits and psychopathic callous-unemotional traits. PLoS One 10 (9), e0134331. ISSN 1932-6203.

Sieradzka, D. and Power, R.A. and Freeman, D. and Cardno, A.G. and Dudbridge, F. and Ronald, Angelica (2015) Heritability of individual psychotic experiences captured by common genetic variants in a community sample of adolescents. Behavior Genetics 45 (5), pp. 493-502. ISSN 0001-8244.

Taylor, M.J. and Charman, T. and Ronald, Angelica (2015) Where are the strongest associations between autistic traits and traits of ADHD? Evidence from a community-based twin study. European Child & Adolescent Psychiatry 24 (9), pp. 1129-1138. ISSN 1018-8827.

Taylor, M. J. and Gregory, A. M. and Freeman, D. and Ronald, Angelica (2015) Do sleep disturbances and psychotic-like experiences in adolescence share genetic and environmental influences? Journal of Abnormal Psychology 124 (3), pp. 674-684. ISSN 0021-843X.

Shakoor, Sania and Zavos, H. and McGuire, P. and Cardno, A.G. and Freeman, D. and Ronald, Angelica (2015) Psychotic experiences are linked to cannabis use in adolescents in the community because of common underlying environmental risk factors. Psychiatry Research 227 (2-3), pp. 144-151. ISSN 0165-1781.

Papageorgiou, K.A. and Farroni, Teresa and Johnson, Mark H. and Smith, Tim J. and Ronald, Angelica (2015) Individual differences in newborn visual attention associate with temperament and behavioral difficulties in later childhood. Scientific Reports 5 , p. 11264. ISSN 2045-2322.

Shakoor, Sania and McGuire, P. and Cardno, A.G. and Freeman, D. and Plomin, R. and Ronald, Angelica (2015) A shared genetic propensity underlies experiences of bullying victimization in late childhood and self-rated paranoid thinking in adolescence.Schizophrenia Bulletin 41 (3), pp. 754-763. ISSN 0586-7614.

Ronald, Angelica (2015) Recent quantitative genetic research on psychotic experiences: new approaches to old questions. Current Opinion in Behavioral Sciences 2 , pp. 81-88. ISSN 2352-1546.

Colvert, E. and Tick, B. and McEwen, F. and Stewart, C. and Curran, S.R. and Woodhouse, E. and Gillan, N. and Hallett, V. and Lietz, S.and Garnett, T. and Ronald, Angelica and Plomin, R. and Rijsdijk, F. and Happé, F. and Bolton, P. (2015) Heritability of autism spectrum disorder in a UK population-based twin sample. JAMA Psychiatry 72 (5), pp. 415-423. ISSN 2168-622X.

Taylor, M.J. and Robinson, E.B. and Happé, F. and Bolton, P. and Freeman, D. and Ronald, Angelica (2015) A longitudinal twin study of the association between childhood autistic traits and psychotic experiences in adolescence. Molecular Autism 6 (1), ISSN 2040-2392.

Taylor, M.J. and Charman, T. and Robinson, E.B. and Hayiou-Thomas, M.E. and Happé, F. and Dale, P.S. and Ronald, Angelica (2014)Language and traits of autism spectrum conditions: evidence of limited phenotypic and etiological overlap. American Journal of Medical Genetics Part B: Neuropsychiatric Genetics 165 (7), pp. 587-595. ISSN 1552-4841.

Zavos, H. and Freedman, D. and Haworth, C. and McGuire, P. and Plomin, R. and Cardno, A.G. and Ronald, Angelica (2014) Consistent etiology of severe, frequent psychotic experiences and milder, less frequent manifestations: a twin study of specific psychotic experiences in adolescence. JAMA Psychiatry 71 (9), pp. 1049-1057. ISSN 2168-622X.

Ronald, Angelica and Sieradzka, D. and Cardno, A.G. and Haworth, C. and McGuire, P. and Freeman, D. (2014) Characterization of psychotic experiences in adolescence using the Specific Psychotic Experiences Questionnaire (SPEQ): findings from a study of 5000 16-year-old twins. Schizophrenia Bulletin 40 (4), pp. 868-877. ISSN 0586-7614.

Papageorgiou, Kostas A. and Smith, Tim J. and Wu, Rachel and Johnson, Mark H. and Kirkham, Natasha Z. and Ronald, Angelica (2014)Individual differences in infant fixation duration relate to attention and behavioral control in childhood. Psychological Science 25 (7), pp. 1371-1379. ISSN 0956-7976.

Willfors, C. and Poltrago, L. and Berggren, S. and Coco, C. and Anckarsäter, H. and Lichtenstein, P. and Ronald, Angelica and Bölte, S.(2014) On the role of non-shared environment for executive functioning in ADHD: a twin-differences design study. International Journal of Developmental Disabilities 60 (3), pp. 163-173. ISSN 2047-3869.

O'nions, E. and Viding, E. and Greven, C.U. and Ronald, Angelica and Happé, F. (2014) Pathological Demand Avoidance (PDA): exploring the behavioural profile. Autism 18 (5), pp. 538-544. ISSN 1362-3613.

St Pourcain, B. and Haworth, C.M.A. and Davis, O.S.P. and Wang, K. and Timpson, N.J. and Evans, D.M. and Kemp, John P. and Ronald, Angelica and Price, T.S and Meaburn, Emma L. and Ring, S.M. and Golding, J. and Hakonarson, H. and Plomin, R. and Davey Smith, G.(2014) Heritability and genome‐wide analyses of problematic peer relationships during childhood and adolescence. Human Genetics134 (6), pp. 539-551. ISSN 0340-6717.

Bölte, S. and Berggren, S. and Norberg, J. and Poltrago, L. and Mevel, K. and Coco, C. and Fransson, P. and Borg, J. and Sitnikov, R. and Toro, R. and Tammimies, K. and Anderlid, B.-A. and Nordgren, A. and Falk, A. and Meyer, U. and Kere, J. and Landén, M. and Dalman, C.and Ronald, Angelica and Anckarsäter, H. and Lichtenstein, P. (2014) The Roots of Autism and ADHD Twin Study in Sweden (RATSS).Twin Research and Human Genetics 17 (03), pp. 164-176. ISSN 1832-4274.

Bölte, S. and Willfors, C. and Berggren, S. and Norberg, J. and Poltrago, L. and Mevel, K. and Coco, C. and Fransson, P. and Borg, J. and Sitnikov, R. and Toro, R. and Tammimies, K. and Anderlid, B.-M. and Nordgren, A. and Falk, A. and Meyer, U. and Kere, J. and Landén, M.and Dalman, C. and Ronald, Angelica and Anckarsäter, H. and Lichtenstein, P. (2014) The roots of autism and ADHD twin study in Sweden (RATSS). Twin Research and Human Genetics 17 (03), pp. 164-176. ISSN 1832-4274.

Ronald, Angelica and Larsson, H. and Anckarsäter, H. and Lichtenstein, P. (2014) Symptoms of autism and ADHD: a Swedish twin study examining their overlap. Journal of Abnormal Psychology 123 (2), pp. 440-451. ISSN 0021-843X.

Scherff, Aline and Taylor, M. and Eley, T.C. and Happé, F. and Charman, T. and Ronald, Angelica (2014) What causes internalising traits and autistic traits to co-occur in adolescence? A community-based twin study. Journal of Abnormal Child Psychology 42 (4), pp. 601-610. ISSN 0091-0627.

Sieradzka, D. and Power, R.A. and Freedman, D. and Cardno, A.G. and McGuire, P. and Plomin, R. and Meaburn, Emma L. and Ronald, Angelica (2014) Are genetic risk factors for psychosis also associated with dimension-specific psychotic experiences in adolescence?PLoS One , ISSN 1932-6203.

Wong, C.C.Y. and Meaburn, Emma L. and Ronald, Angelica and Price, T.S and Jeffries, A.R. and Schalkwyk, L.C. and Plomin, R. and Mill, J.(2014) Methylomic analysis of monozygotic twins discordant for autism spectrum disorder and related behavioural traits. Molecular Psychiatry 19 (4), pp. 495-503. ISSN 1359-4184.

Holmboe, Karla and Rijsdijk, F. and Hallett, V. and Happé, F. and Plomin, R. and Ronald, Angelica (2014) Strong genetic influences on the stability of autistic traits in childhood. Journal of the American Academy of Child and Adolescent Psychiatry 53 (2), pp. 221-230. ISSN 0890-8567.

Nguyen, C. and Ronald, Angelica (2014) Are autism spectrum disorders comparable in boys and girls? An examination of sex differences in behaviour, cognition and psychopathology in a predominantly low functioning sample. Scandinavian Journal of Child and Adolescent Psychiatry and Psychology 2 (2), pp. 55-65. ISSN 2245-8875.

Thomas, Michael S. C. and Forrester, Neil A. and Ronald, Angelica (2013) Modeling socioeconomic status effects on language development. Developmental Psychology 49 (12), pp. 2325-2343. ISSN 0012-1649.

Hallett, V. and Ronald, Angelica and Colvert, E. and Ames, C. and Woodhouse, E. and Lietz, S. and Garnett, T. and Gillan, N. and Rijsdijk, F. and Scahill, L. and Bolton, P. and Happé, F. (2013) Exploring anxiety symptoms in a large-scale twin study of children with autism spectrum disorders, their co-twins and controls. Journal of Child Psychology and Psychiatry 54 (11), pp. 1176-1185. ISSN 0021-9630.

Taylor, M.J. and Charman, T. and Robinson, E.B. and Plomin, R. and Happé, F. and Asherson, P. and Ronald, Angelica (2013)Developmental associations between traits of autism spectrum disorder and attention-deficit/hyperactivity disorder: a genetically-informative, longitudinal twin study. Psychological Medicine 43 (08), pp. 1735-1746. ISSN 0033-2917.

Robinson, E.B. and Lichtenstein, P. and Anckarsäter, H. and Happé, F. and Ronald, Angelica (2013) Examining and interpreting the female protective effect against autistic behavior. Proceedings of the National Academy of Sciences of the United States of America110 (13), pp. 5258-5262. ISSN 0027-8424.

Papageorgiou, K.A. and Ronald, Angelica (2013) "He who sees things grow from the beginning will have the finest view of them": a systematic review of genetic studies on psychological traits in infancy. Neuroscience & Biobehavioral Reviews 37 (8), pp. 1500-1517. ISSN 0149-7634.

Dworzynski, K. and Ronald, Angelica and Bolton, P. and Happé, F. (2012) How different are girls and boys above and below the diagnostic threshold for Autism Spectrum Disorders? Journal of the American Academy of Child and Adolescent Psychiatry 51 (8), pp. 788-797. ISSN 0890-8567.

Hallett, V. and Ronald, Angelica and Rijsdijk, F. and Happé, F. (2012) Disentangling the associations between autistic-like and internalizing traits: a community based twin study. Journal of Abnormal Child Psychology 40 (5), pp. 815-827. ISSN 0091-0627.

Robinson, E.B. and Koenen, K.C. and McCormick, M.C. and Munir, K. and Hallett, V. and Happé, F. and Plomin, R. and Ronald, Angelica(2012) A multivariate twin study of autistic traits in 12-year-olds: testing the fractionable autism triad hypothesis. Behavior Genetics 42 (2), pp. 245-255. ISSN 0001-8244.

Robinson, E.B. and Koenen, K.C. and McCormick, M.C. and Munir, K. and Hallett, V. and Happé, F. and Plomin, R. and Ronald, Angelica(2011) Evidence that autistic traits show the same etiology in the general population and at the quantitative extremes (5%, 2.5%, and 1%). Archives of General Psychiatry 68 (11), pp. 1113-1121. ISSN 0003-990X.

Ronald, Angelica (2011) Is the child ‘father of the Man’? Evaluating the stability of genetic influences across development.Developmental Science 14 (6), pp. 1471-1478. ISSN 1363-755x.

Curran, S. and Dworzynski, K. and Happé, F. and Ronald, Angelica and Allison, C. and Baron-Cohen, S. and Brayne, C. and Bolton, P.F.(2011) No major effect of twinning on autistic traits. Autism Research 4 (5), pp. 377-382. ISSN 1939-3792.

Ronald, Angelica and Larsson, H. and Anckarsäter, H. and Lichtenstein, P. (2011) A twin study of autism symptoms in Sweden.Molecular Psychiatry 16 (10), pp. 1039-1047. ISSN 1359-4184.

Whitehouse, A.J.O. and Hickey, M. and Ronald, Angelica (2011) Are autistic traits in the general population stable across development?PLoS One 6 (8), ISSN 1932-6203.

Ronald, Angelica and Hoekstra, R.A. (2011) Autism spectrum disorders and autistic traits: a decade of new twin studies. American Journal of Medical Genetics Part B: Neuropsychiatric Genetics 156B (3), pp. 255-74. ISSN 1552-4841.

Ronald, Angelica and Pennell, C.E. and Whitehouse, A.J.O. (2011) Prenatal maternal stress associated with ADHD and autistic traits in early childhood. Frontiers in Psychology 1 (223), ISSN 1664-1078.

Ronald, Angelica (2011) Is the child 'father of the Man': evaluating the stability of genetic influences across development.Developmental Science 14 (6), pp. 1471-8. ISSN 1363-755x.

Moruzzi, S. and Ogliari, A. and Ronald, Angelica and Happé, F. and Battaglia, M. (2011) The nature of covariation between autistic traits and clumsiness: a twin study in a general population sample. Journal of Autism and Developmental Disorders 41 (12), pp. 1665-1674. ISSN 0162-3257.

Hallett, V. and Ronald, Angelica and Rijsdijk, F. and Happé, F. (2010) Association of autistic-like and internalizing traits during childhood: a longitudinal twin study. American Journal of Psychiatry 167 (7), pp. 809-817. ISSN 0002-953X.

Ronald, Angelica and Edelson, L.R. and Asherson, P. and Saudino, K.J. (2010) Exploring the relationship between autistic-like traits and ADHD behaviors in early childhood: findings from a community twin study of 2-year-olds. Journal of Abnormal Child Psychology 38 (2), pp. 185-196. ISSN 0091-0627.

Ronald, Angelica and Happé, F. and Dworzynski, K. and Bolton, P. and Plomin, R. (2010) Exploring the relation between prenatal and neonatal complications and later autistic-Like features in a representative community sample of twins. Child Development 81 (1), pp. 166-182. ISSN 0009-3920.

Ronald, Angelica and Butcher, L.M. and Docherty, S.J. and Davis, O.S.P. and Schalkwyk, L.C. and Craig, I.W. and Plomin, R. (2010)Response to comment by Stuart Macgregor. Behavior Cognition 40 (1), p. 48. ISSN 0001-8244.

Ronald, Angelica and Butcher, L.M. and Docherty, S.J. and Davis, O.S.P. and Schalkwyk, L.C. and Craig, I.W. and Plomin, R. (2010) A genome-wide association study of social and non-social autistic-like traits in the general population using pooled DNA, 500 K SNP microarrays and both community and diagnosed autism replication samples. Behavior Genetics 40 (1), pp. 31-45. ISSN 0001-8244.

Ronald, Angelica and Hoekstra, R.A. and Happé, F. and Baron-Cohen, S. (2010) Limited genetic covariance between autistic traits and intelligence: findings from a longitudinal twin study. American Journal of Medical Genetics Part B: Neuropsychiatric Genetics 153b (5), pp. 994-1007. ISSN 1552-4841.

Ronald, Angelica and Lundstrom, S. and Haworth, C. and Carlström, E. and Gillberg, C. and Mill, J. and Råstam, M. and Hultman, C. and Anckarsäter, H. and Plomin, R. and Lichtenstein, P. and Reichenberg, A. (2010) Trajectories leading to autism spectrum disorders are affected by paternal age: findings from two nationally representative twin studies. Journal of Child Psychology and Psychiatry 51 (7), pp. 850-856. ISSN 0021-9630.

Hoekstra, R.A. and Happé, F. and Baron-Cohen, S. and Ronald, Angelica (2009) Association between extreme autistic traits and intellectual disability: insights from a general population twin study. British Journal of Psychiatry 195 (6), pp. 531-536. ISSN 0007-1250.

Jones, A.P. and Larsson, H. and Ronald, Angelica and Rijsdijk, F. and Busfield, P. and Mcmillan, A. and Plomin, R. and Viding, E. (2009)Phenotypic and aetiological associations between psychopathic tendencies, autistic traits, and emotion attribution. Criminal Justice and Behavior 36 (11), pp. 1198-1212. ISSN 0093-8548.

Vital, P.M. and Ronald, Angelica and Wallace, G.L. and Happé, F. (2009) Relationship between special abilities and autistic-like traits in a large population-based sample of 8-year-olds. Journal of Child Psychology and Psychiatry and Allied Disciplines 50 (9), pp. 1093-1101. ISSN 0021-9630.

Dworzynski, K. and Happé, F. and Bolton, P. and Ronald, Angelica (2009) Relationship between symptom domains in autism spectrum disorders: a population based twin study. Journal of Autism and Developmental Disorders 39 (8), pp. 1197-1210. ISSN 0162-3257.

Hallett, V. and Ronald, Angelica and Happé, F. (2009) Investigating the association between autistic-like and internalizing traits in a community-based twin sample. Journal of the American Academy of Child and Adolescent Psychiatry 48 (6), pp. 618-627. ISSN 0890-8567.

Hallett, V. and Ronald, Angelica and Rijsdijk, F. and Eley, T.C. (2009) Phenotypic and genetic differentiation of anxiety-related behaviors in middle childhood. Depression and Anxiety 26 (4), pp. 316-324. ISSN 1091-4269.

Happé, F. and Ronald, Angelica (2008) The 'Fractionable Autism Triad': a review of evidence from behavioural, genetic, cognitive and neural research. Neuropsychology Review 18 (4), pp. 287-304. ISSN 1040-7308.

Ronald, Angelica and Happé, F. and Plomin, R. (2008) A twin study investigating the genetic and environmental aetiologies of parent, teacher and child ratings of autistic-like traits and their overlap. European Child & Adolescent Psychiatry 17 (8), pp. 473-483. ISSN 1018-8827.

Hoekstra, R.A. and Ronald, Angelica and Happé, F. and Baron-Cohen, S. and Plomin, R. (2008) Genetic influences on extreme autistic traits and intellectual impairment: overlap and specificity. Behavior Genetics 38 (6), pp. 630-631. ISSN 0001-8244.

Ronald, Angelica and Simonoff, E. and Kuntsi, J. and Asherson, P. and Plomin, R. (2008) Evidence for overlapping genetic influences on autistic and ADHD behaviours in a community twin sample. Journal of Child Psychology and Psychiatry and Allied Disciplines 49 (5), pp. 535-542. ISSN 0021-9630.

Dworzynski, K. and Ronald, Angelica and Hayiou-Thomas, M.E. and McEwan, F. and Happé, F. and Bolton, P. and Plomin, R. (2008)Developmental path between language and autistic-like impairments: a twin study. Infant and Child Development 17 (2), pp. 121-136. ISSN 1099-0917.

Book Section

Ronald, Angelica and Hoekstra, R.A. (2014) Progress in understanding the causes of autism spectrum disorders and autistic traits: twin studies from 1977 to the present day. In: Ronald, Angelica and Rhee, S.H. (eds.) Behavior Genetics of Psychopathology. Advances in Behavior Genetics 2. New York, U.S.: Springer, pp. 33-65. ISBN 9781461495086.