Alexandra Havdahl

• Eilertsen, Espen Moen; Jami, Eshim Shahid; McAdams, Tom A.; Hannigan, Laurie J.; Havdahl, Alexandra; Magnus, Per; Evans, David M. & Ystrøm, Eivind (2021). Direct and Indirect Effects of Maternal, Paternal, and Offspring Genotypes: Trio-GCTA. Behavior Genetics.  ISSN 0001-8244.  s 1- 8 . doi: 10.1007/s10519-020-10036-6
• Hannigan, Laurie John; Askeland, Ragna Bugge; Ask, Helga; Tesli, Martin Steen; Corfield, Elizabeth; Lennox, Ziada Ayorech; Helgeland, Øyvind; Magnus, Per; Njølstad, Pål Rasmus; Øyen, Anne-Siri; Stoltenberg, Camilla; Andreassen, Ole Andreas; Davey smith, George; Reichborn-Kjennerud, Ted & Havdahl, Alexandra (2021). Genetic Liability for Schizophrenia and Childhood Psychopathology in the General Population. Schizophrenia Bulletin.  ISSN 0586-7614.
• Havdahl, Alexandra; Niarchou, Maria; Starnawska, A; Uddin, M; van der Merwe, Celia & Warrier, Varun (2021). Genetic contributions to autism spectrum disorder. Psychological Medicine.  ISSN 0033-2917. . doi: https://doi.org/10.1017/S0033291721000192 Show summary

  Autism spectrum disorder (autism) is a heterogeneous group of neurodevelopmental conditions characterized by early childhood-onset impairments in communication and social interaction alongside restricted and repetitive behaviors and interests. This review summarizes recent developments in human genetics research in autism, complemented by epigenetic and transcriptomic findings. The clinical heterogeneity of autism is mirrored by a complex genetic architecture involving several types of common and rare variants, ranging from point mutations to large copy number variants, and either inherited or spontaneous (de novo). More than 100 risk genes have been implicated by rare, often de novo, potentially damaging mutations in highly constrained genes. These account for substantial individual risk but a small proportion of the population risk. In contrast, most of the genetic risk is attributable to common inherited variants acting en masse, each individually with small effects. Studies have identified a handful of robustly associated common variants. Different risk genes converge on the same mechanisms, such as gene regulation and synaptic connectivity. These mechanisms are also implicated by genes that are epigenetically and transcriptionally dysregulated in autism. Major challenges to understanding the biological mechanisms include substantial phenotypic heterogeneity, large locus heterogeneity, variable penetrance, and widespread pleiotropy. Considerable increases in sample sizes are needed to better understand the hundreds or thousands of common and rare genetic variants involved. Future research should integrate common and rare variant research, multi-omics data including genomics, epigenomics, and transcriptomics, and refined phenotype assessment with multidimensional and longitudinal measures.

• Akingbuwa, Wonuola A.; Hammerschlag, Anke R.; Jami, Eshim S.; Allegrini, Andrea G.; Karhunen, Ville; Sallis, Hannah; Ask, Helga; Askeland, Ragna Bugge; Baselmans, Bart; Diemer, Elizabeth W; Hagenbeek, Fiona A.; Havdahl, Alexandra; Hottenga, Jouke-Jan; Mbarek, Hamdi; Rivadeneira, Fernando; Tesli, Martin Steen; van Beijsterveldt, Catharina E. M.; Breen, Gerome; Lewis, Cathryn M.; Thapar, Anita; Boomsma, Dorret I.; Kuja-Halkola, Ralf; Reichborn-Kjennerud, Ted; Magnus, Per; Rimfeld, Kaili; Ystrøm, Eivind; Järvelin, Marjo-Riitta; Lichtenstein, Paul; Lundström, Sebastian; Munafò, Marcus R.; Plomin, Robert; Tiemeier, Henning; Nivard, Michel G.; Bartels, Meike & Middeldorp, Christel M. (2020). Genetic Associations Between Childhood Psychopathology and Adult Depression and Associated Traits in 42 998 Individuals: A Meta-analysis. JAMA psychiatry.  ISSN 2168-6238.  77(7), s 715- 728 . doi: 10.1001/jamapsychiatry.2020.0527 Full text in Research Archive.
• Brumpton, Ben Michael; Sanderson, Eleanor; Heilbron, Karl; Hartwig, FP; Harrison, S; Vie, Gunnhild Åberge; Cho, Y; Howe, LD; Hughes, A; Boomsma, D; Havdahl, Alexandra; Hopper, J; Neale, M; Nivard, Michel G.; Pedersen, N; Reynolds, CA; Tucker-D, EM; Grotzinger, A; Howe, Laurence; Morris, Tim; Li, Shuai; Within-Family Consortium, The; 23andMe Research Team, The; Auton, A; Windmeijer, F; Chen, W-M; Bjørngaard, Johan Håkon; Hveem, Kristian; Willer, C; Evans, DM; Kaprio, J; Davey Smith, G; Åsvold, Bjørn Olav; Hemani, G & Davies, Neil Martin (2020). Avoiding dynastic, assortative mating, and population stratification biases in Mendelian randomization through within-family analyses. Nature Communications.  ISSN 2041-1723.  11 . doi: 10.1038/s41467-020-17117-4 Full text in Research Archive.
• Cheesman, Rosa; Eilertsen, Espen Moen; Ahmadzadeh, Yasmin I.; Gjerde, Line C.; Hannigan, Laurie John; Havdahl, Alexandra; Young, Alexander I.; Eley, Thalia C.; Njølstad, Pål Rasmus; Magnus, Per; Andreassen, Ole Andreas; Ystrøm, Eivind & McAdams, Tom A. (2020). How important are parents in the development of child anxiety and depression? A genomic analysis of parent-offspring trios in the Norwegian Mother Father and Child Cohort Study (MoBa). BMC Medicine.  ISSN 1741-7015.  18 . doi: 10.1186/s12916-020-01760-1 Full text in Research Archive.
• Havdahl, Alexandra; Farmer, Cristan; Schjølberg, Synnve; Øyen, Anne-Siri; Suren, Pål; Reichborn-Kjennerud, Ted; Magnus, Per; Bresnahan, Michaeline; Hornig, Mady; Susser, Ezra; Lipkin, Walter Ian; Lord, Catherine; Stoltenberg, Camilla; Thurm, Audrey & Bishop, Somer L. (2020). Age of walking and intellectual ability in autism spectrum disorder and other neurodevelopmental disorders: a population‐based study. Journal of Child Psychology and Psychiatry.  ISSN 0021-9630.  s 1- 9 . doi: 10.1111/jcpp.13369 Full text in Research Archive.
• Kiselev, Yury; Handal, Marte; Hjellvik, Vidar; Reichborn-Kjennerud, Ted; Stoltenberg, Camilla; Suren, Pål; Havdahl, Alexandra & Skurtveit, Svetlana (2020). Nationwide study of neuropsychiatric comorbidity and medicines use in children with autism spectrum disorder in Norway. Frontiers in Psychiatry.  ISSN 1664-0640.  11, s 1- 8 . doi: 10.3389/fpsyt.2020.596032
• Sallis, Hannah M.; Croft, Jazz; Havdahl, Alexandra; Jones, Hannah J.; Dunn, Erin C.; Smith, George Davey; Zammit, Stanley & Munafò, Marcus R. (2020). Genetic liability to schizophrenia is associated with exposure to traumatic events in childhood. Psychological Medicine.  ISSN 0033-2917. . doi: 10.1017/S0033291720000537
• Torvik, Fartein Ask; Eilertsen, Espen Moen; McAdams, Tom A.; Gustavson, Kristin; Zachrisson, Henrik Daae; Brandlistuen, Ragnhild Eek; Gjerde, Line C.; Havdahl, Alexandra; Stoltenberg, Camilla; Ask, Helga & Ystrøm, Eivind (2020). Mechanisms linking parental educational attainment with child ADHD, depression, and academic problems: a study of extended families in The Norwegian Mother, Father and Child Cohort Study. Journal of Child Psychology and Psychiatry.  ISSN 0021-9630.  61(9), s 1009- 1018 . doi: 10.1111/jcpp.13197 Full text in Research Archive.
• Davies, Neil M.; Howe, Laurence; Brumpton, Ben Michael; Havdahl, Alexandra; Evans, David M. & Smith, George Davey (2019). Within family Mendelian randomization studies. Human Molecular Genetics.  ISSN 0964-6906.  28(2), s R170- R179 . doi: 10.1093/hmg/ddz204
• Havdahl, Alexandra; Ruth, Mitchell; Lavinia, Paternoster & Davey Smith, George (2019). Investigating causality in the association between vitamin D status and self-reported tiredness. Scientific Reports.  ISSN 2045-2322.  9 . doi: 10.1038/s41598-019-39359-z Full text in Research Archive.
• Leppert, Beate; Havdahl, Alexandra; Riglin, Lucy; Jones, Hannah J.; Zheng, Jie; Davey Smith, George; Tilling, Kate; Thapar, Anita; Reichborn-Kjennerud, Ted & Stergiakouli, Evie (2019). Association of maternal neurodevelopmental risk alleles with early-life exposures. JAMA psychiatry.  ISSN 2168-6238.  76(8), s 834- 842 . doi: 10.1001/jamapsychiatry.2019.0774 Full text in Research Archive.
• Suren, Pål; Havdahl, Alexandra; Bresnahan, Michaeline; Hirtz, Deborah; Hornig, Mady; Lord, Catherine; Reichborn-Kjennerud, Ted; Schjølberg, Synnve; Øyen, Anne-Siri; Magnus, Per; Susser, Ezra; Lipkin, W. Ian & Stoltenberg, Camilla (2019). Sensitivity and specificity of early screening for autism. BJPsych Open.  ISSN 2056-4724.  5(3) . doi: 10.1192/bjo.2019.34 Full text in Research Archive.
• Suren, Pål; Havdahl, Alexandra; Øyen, Anne-Siri; Schjølberg, Synnve; Reichborn-Kjennerud, Ted; Magnus, Per; Bakken, Inger Johanne Landsjøåsen & Stoltenberg, Camilla (2019). Diagnostisering av autismespekterforstyrrelser hos barn i Norge. Tidsskrift for Den norske legeforening.  ISSN 0029-2001.  139(14), s 1372- 1379 . doi: 10.4045/tidsskr.18.0960 Full text in Research Archive. Show summary

  BACKGROUND:The percentage share of children who are diagnosed with autism spectrum disorder has increased considerably since the 1990s in Norway as well as in other countries. It has previously been demonstrated that there is considerable variation between counties with respect to diagnostic practice. MATERIAL AND METHOD:We calculated the percentage of children with autism spectrum disorder by using patient data obtained from the Norwegian Patient Registry and population data obtained from the National Registry. The calculations were made for the country as a whole as well as by county. The diagnostic assessments and documentation were mapped by linking the Norwegian Patient Registry with the Norwegian Mother, Father and Child Cohort study. We also reviewed patient records obtained from the specialist health service and considered whether diagnostic practice satisfied the research criteria for autism spectrum disorder. RESULTS:By the age of eight, 1.1 % of boys and 0.3 % of girls had been diagnosed with autism spectrum disorder. The overall percentages varied from 0.3 to 1.0 between counties. From 2008 to 2016, these percentages increased in all age groups. Our review of patient records included 503 children. In 95 % of cases the patient records provided a high standard of documentation that the diagnostic research criteria had been satisfied. The assessments were largely conducted in accordance with the guidelines drawn up by the various health trusts. INTERPRETATION:Autism diagnoses are generally well documented within the Norwegian specialist health service and meet the diagnostic criteria. In the counties that demonstrate a low prevalence of autism, it appears the health service fails to recognise autism in many children, particularly girls, or the diagnosis is determined late.

• Ask, Helga; Gustavson, Kristin; Ystrøm, Eivind; Havdahl, Karoline Alexandra; Tesli, Martin Steen; Askeland, Ragna Bugge & Reichborn-Kjennerud, Ted (2018). Association of Gestational Age at Birth With Symptoms of Attention-Deficit/Hyperactivity Disorder in Children. JAMA pediatrics.  ISSN 2168-6203.  172(8), s 749- 756 . doi: 10.1001/jamapediatrics.2018.1315
• Caramaschi, Doretta; Taylor, Amy; Richmond, Rebecca C.; Havdahl, Alexandra; Golding, Jean; Relton, Caroline; Munafo, Marcus R; Davey Smith, George & Rai, Dheeraj (2018). Maternal smoking during pregnancy and autism: using causal inference methods in a birth cohort study. Translational Psychiatry.  ISSN 2158-3188.  8(262) . doi: 10.1038/s41398-018-0313-5
• Øien, Roald A; Schjølberg, Synnve; Volkmar, Fred R.; Shic, Frederick; Cicchetti, Domenic V.; Nordahl-Hansen, Anders Johan; Stenberg, Nina; Hornig, Mady; Havdahl, Karoline Alexandra; Øyen, Anne-Siri; Ventola, Pamela; Susser, Ezra S.; Eisemann, Martin & Chawarska, Katarzyna (2018). Clinical Features of Children With Autism Who Passed 18-Month Screening. Pediatrics.  ISSN 0031-4005.  141(6) . doi: 10.1542/peds.2017-3596 Full text in Research Archive.
• Bishop, Somer L.; Farmer, Cristan; Hus Bal, Vanessa; Robinson, Elise; Willsey, AJ; Werling, DM; Havdahl, Karoline Alexandra; Sanders, SJ & Thurm, A. (2017). Identification of Developmental and Behavioral Markers Associated With Genetic Abnormalities in Autism Spectrum Disorder. American Journal of Psychiatry.  ISSN 0002-953X.  174(6), s 576- 585 . doi: 10.1176/appi.ajp.2017.16101115
• Bishop, Somer L.; Huerta, Marisela; Gotham, K.; Havdahl, Karoline Alexandra; Pickles, Andrew; Duncan, A.; Hus Bal, Vanessa; Croen, L. & Lord, Catherine (2017). The autism symptom interview, school-age: A brief telephone interview to identify autism spectrum disorders in 5-to-12-year-old children. Autism Research.  ISSN 1939-3792.  10(1), s 78- 88 . doi: 10.1002/aur.1645
• Havdahl, Karoline Alexandra; Bishop, Somer L.; Surén, Pål; Øyen, Anne-Siri; Lord, Catherine; Pickles, Andrew; von Tetzchner, Stephen; Schjølberg, Synnve; Gunnes, Nina; Hornig, Mady; Lipkin, W. Ian; Susser, Ezra; Bresnahan, Michaeline; Magnus, Per; Stenberg, Nina; Reichborn-Kjennerud, Ted & Stoltenberg, Camilla (2017). The influence of parental concern on the utility of autism diagnostic instruments. Autism Research.  ISSN 1939-3792.  10(10), s 1672- 1686 . doi: 10.1002/aur.1817
• Bishop, Somer L.; Havdahl, Alexandra; Huerta, Marisela & Lord, Catherine (2016). Subdimensions of social-communication impairment in autism spectrum disorder. Journal of Child Psychology and Psychiatry.  ISSN 0021-9630.  57(8), s 909- 916 . doi: 10.1111/jcpp.12510
• Havdahl, Alexandra; Tetzchner, Stephen von; Huerta, Marisela; Lord, Catherine & Bishop, Somer L. (2016). Utility of the Child Behavior Checklist as a Screener for Autism Spectrum Disorder. Autism Research.  ISSN 1939-3792.  9(1), s 33- 42 . doi: 10.1002/aur.1515
• Havdahl, Karoline Alexandra; Hus Bal, Vanessa; Huerta, Marisela; Pickles, Andrew; Øyen, Anne-Siri; Stoltenberg, Camilla; Lord, Catherine & Bishop, Somer L. (2016). Multidimensional influences on autism symptom measures: Implications for use in etiological research. Journal of the American Academy of Child and Adolescent Psychiatry.  ISSN 0890-8567.  55(12), s 1054- 1063 . doi: 10.1016/j.jaac.2016.09.490

View all works in Cristin

• Hannigan, Laurie John & Havdahl, Alexandra (2021). Meeting the challenge of multidimensionality in neurodevelopmental disorders – reflections on Johnson et al. (2021). Journal of Child Psychology and Psychiatry.  ISSN 0021-9630. . doi: 10.1111/jcpp.13416
• Askeland, Ragna Bugge; Hannigan, Laurie John; Ask, Helga; Lennox, Ziada Ayorech; Tesli, Martin Steen; Corfield, Elizabeth; Davey-Smith, George; Reichborn-Kjennerud, Ted & Havdahl, Alexandra (2020). Genetic risk factors for neurodevelopmental disorders.
• Askeland, Ragna Bugge; Hannigan, Laurie John; Ask, Helga; Lennox, Ziada Ayorech; Tesli, Martin Steen; Corfield, Elizabeth; Magnus, Per; Njølstad, Pål Rasmus; Andreassen, Ole Andreas; Davey smith, George; Reichborn-Kjennerud, Ted & Havdahl, Alexandra (2020). Early manifestations of genetic risk for neurodevelopmental disorders.
• Hannigan, Laurie John; Askeland, Ragna Bugge; Ask, Helga; Tesli, Martin Steen; Corfield, Elizabeth; Lennox, Ziada Ayorech; Magnus, Per; Njølstad, Pål Rasmus; Øyen, Anne-Siri; Stoltenberg, Camilla; Andreassen, Ole Andreas; Davey smith, George; Reichborn-Kjennerud, Ted & Havdahl, Alexandra (2020). Developmental milestones in early childhood and genetic liability to neurodevelopmental disorders.
• Havdahl, Alexandra (2020). Autism and autistic traits in the Norwegian Mother, Father and Child Cohort Study (MoBa).
• Havdahl, Alexandra (2020). PaGE and PsychGen: The Psychiatric Genetic Epidemiology group.
• Havdahl, Alexandra (2020). Update on psychiatric genetics research in the Norwegian Mother, Father and Child Cohort Study.
• Havdahl, Alexandra; Niarchou, M; Starnawska, A & van der Merwe, Celia (2020). Genetic contributions to autism spectrum disorder.
• Lennox, Ziada Ayorech; Davies, Neil; Hannigan, Laurie John; Askeland, Ragna Bugge; Tesli, Martin Steen; Andreassen, Ole Andreas; Reichborn-Kjennerud, Ted; Helgeland, Øyvind; Johansson, Stefan; Njølstad, Pål Rasmus; Ask, Helga; Davey Smith, George; Bulik, Cynthia & Havdahl, Alexandra (2020). Which Metabo-Psychiatric Factors Affect the Risk of Anorexia Nervosa? A Mendelian Randomization Study.
• Torvik, Fartein Ask; Eilertsen, Espen Moen; Hannigan, Laurie John; Havdahl, Alexandra & Ystrøm, Eivind (2020). Assortative mating and the usefulness of polygenic scores in extended pedigrees.
• Ask, Helga; Eilertsen, Espen Moen; Gjerde, Line C.; Gustavson, Kristin; Hannigan, Laurie John; Havdahl, Alexandra; McAdams, Tom A.; Hettema, John M.; Reichborn-Kjennerud, Ted; Torvik, Fartein Ask & Ystrøm, Eivind (2019). Intergenerational transmission of parental neuroticism to offspring neuroticism, depression, and anxiety.
• Ask, Helga; Eilertsen, Espen Moen; Gjerde, Line C.; Gustavson, Kristin; Hannigan, Laurie John; Havdahl, Alexandra; McAdams, Tom A.; Hettema, John M.; Reichborn-Kjennerud, Ted; Torvik, Fartein Ask & Ystrøm, Eivind (2019). Intergenerational transmission of parental neuroticism to offspring neuroticism, depression, and anxiety. Behavior Genetics.  ISSN 0001-8244.  49(6), s 548- 548 . doi: 10.1007/s10519-019-09973-8
• Ask, Helga; Hannigan, Laurie; Davies, Neil; Gustavson, Kristin; Biele, Guido; Richardson, Thomas; Cornish, Rosie; Corfield, Elizabeth; Askeland, Ragna Bugge; Tesli, Martin Steen; Tilling, Kate; Davey Smith, George; Magnus, Per; Reichborn-Kjennerud, Ted & Havdahl, Alexandra (2019). Exploring the Associations Between Health-Related Polygenic Scores and Participation in the Norwegian Mother and Child Pregnancy Cohort (MoBa).
• Askeland, Ragna Bugge; Hannigan, Laurie John; Ask, Helga; Tesli, Martin Steen; Corfield, Elizabeth; Andreassen, Ole Andreas; Davey-Smith, George; Reichborn-Kjennerud, Ted & Havdahl, Alexandra (2019). Early manifestations of genetic risk for neurodevelopmental disorders.
• Askeland, Ragna Bugge; Reichborn-Kjennerud, Ted; Hannigan, Laurie John; Ask, Helga; Tesli, Martin Steen; Corfield, Elizabeth & Havdahl, Alexandra (2019). Early manifestation of genetic risk for attention deficit/hyperactivity disorder in Norwegian children.
• Cheesman, Rosa; Eilertsen, Espen Moen; Ahmadzadeh, Yasmin; Gjerde, Line C.; Hannigan, Laurie; Havdahl, Alexandra; Eley, Thalia C.; Ystrøm, Eivind & McAdams, Tom A. (2019). Separating child and parent influences on child depression and anxiety using genomic family data.
• Cheesman, Rosa; Eilertsen, Espen Moen; Ahmadzadeh, Yasmin; Gjerde, Line C.; Hannigan, Laurie; Havdahl, Alexandra; Eley, Thalia C.; Ystrøm, Eivind & McAdams, Tom A. (2019). Separating child and parent influences on child depression and anxiety using genomic family data. European Neuropsychopharmacology.  ISSN 0924-977X.  29, s S119- S119 . doi: 10.1016/j.euroneuro.2019.08.012
• Cheesman, Rosa; Eilertsen, Espen Moen; Ahmadzadeh, Yasmin; Gjerde, Line C.; Hannigan, Laurie; Havdahl, Alexandra; Eley, Thalia; Ystrøm, Eivind & McAdams, Tom A. (2019). Separating child and parent influences on child emotional problems using genomic family data.
• Cheesman, Rosa; Eilertsen, Espen Moen; Ahmadzadeh, Yasmin; Gjerde, Line C.; Hannigan, Laurie; Havdahl, Alexandra; Eley, Thalia; Ystrøm, Eivind & McAdams, Tom A. (2019). Separating child and parent influences on child emotional problems using genomic family data. Behavior Genetics.  ISSN 0001-8244.  49(6), s 523- 524 . doi: 10.1007/s10519-019-09973-8
• Hannigan, Laurie; Askeland, Ragna Bugge; Ask, Helga; Tesli, Martin Steen; Corfield, Elizabeth; Mcadams, Tom; Øyen, Anne-Siri; Davey-Smith, George; Reichborn-Kjennerud, Ted & Havdahl, Alexandra (2019). Perinatal maternal stress and early-life behavioural and emotional problems: examining the role of genetically-influenced environmental sensitivity in mothers and offspring.
• Havdahl, Alexandra (2019). Autism in Norway.
• Havdahl, Alexandra (2019). Using population-based cohort studies and nationwide registries to study autism and other neurodevelopmental disorders.
• Havdahl, Alexandra & Bishop, Somer L. (2019). Heterogeneity in prevalence of co-occurring psychiatric conditions in autism. Lancet psychiatry.  ISSN 2215-0374. . doi: https://doi.org/10.1016/S2215-0366(19)30326-8
• Havdahl, Alexandra; Laurie, Hannigan; Askeland, Ragna Bugge; Ask, Helga; Tesli, Martin Steen; Corfield, Elizabeth; Øyen, Anne-Siri; Andreassen, Ole; Davey Smith, George & Reichborn-Kjennerud, Ted (2019). Polygenic Risk for ADHD and Exposures During Pregnancy in the Norwegian Mother and Child Cohort Study (MoBa). Show summary

  Background: Over the past decade, there has been an increase in studies showing associations between a broad range of lifestyle factors (e.g., smoking and alcohol intake) and health-related exposures (e.g., gestational diabetes) in pregnant women and ADHD in their children. It is, however, unclear whether the observed associations are causal or not. They may reflect confounding by unmeasured shared familial factors that influence both the maternal exposure and offspring ADHD. In the present study we assess the potential contribution of maternal polygenic risk for ADHD to pregnancy exposures linked to this disorder. Methods: We use data from the Norwegian Mother and Child pregnancy cohort study (MoBa), a prospective population-based pregnancy cohort study conducted by the Norwegian Institute of Public Health. Participants were recruited from all over Norway from 1999-2008. The women consented to participation in 40.6 % of the pregnancies. The cohort now includes 114,500 children, 95,200 mothers and 75,200 fathers. Blood samples were obtained from both parents during pregnancy and from mothers and children (umbilical cord) at birth. Genotyping is ongoing. A wide range of pregnancy exposures have been measured through the Medical Birth Registry and questionnaires. Summary statistics from the largest available genome-wide association study of ADHD (Demontis et al., 2019) were used to calculate polygenic risk scores (PRS). Results: Preliminary results from up to 9,073 mothers with available genotype and pregnancy exposure data suggest that maternal PRS for ADHD is associated with a range of pregnancy exposures, including smoking, coffee intake, non-use of nutritional supplements and use of pain medications. At WCPG, results will be presented from analyses of more than 20,000 mothers. For comparison purposes, associations between ADHD PRS and lifestyle and health-related factors in fathers (n>20,000) will be shown. Finally, we will present analyses of the extent to which accounting for genetic confounding attenuates associations between maternal pregnancy exposures and offspring ADHD in the MoBa cohort. Discussion: The results indicate that observed associations between pregnancy exposures and offspring ADHD could at least partly be explained by shared genetic influences/gene-environment correlations. Disclosure: Nothing to disclose.

• Skurtveit, Svetlana; Kiselev, Yury; Handal, Marte; Stoltenberg, Camilla; Reichborn-Kjennerud, Ted; Suren, Pål; Havdahl, Alexandra & Hjellvik, Vidar (2019). Co-Occurring Neuropsychiatric Diagnoses and Use of Psychotropic Drugs in Children with Autism Spectrum Disorder. Pharmacoepidemiology and Drug Safety.  ISSN 1053-8569. . doi: 10.10002/pds.4864
• Tesli, Martin Steen; Corfield, Elizabeth; Zayats, Tetyana; Ask, Helga; Askeland, Ragna Bugge; Hannigan, Laurie; Robinson, Elise; Andreassen, Ole Andreas; Havdahl, Alexandra & Reichborn-Kjennerud, Ted (2019). Investigation of shared genetic risk between cardiometabolic morbidity and ADHD in a Norwegian family cohort using polygenic transmission disequilibrium test.
• Havdahl, Alexandra (2018). Challenges in assessment of autism spectrum disorder.
• Havdahl, Alexandra (2018). Gene-Environment Interplay and Mental Health Problems.
• Havdahl, Alexandra (2018). Understanding the development of mental health problems utilizing large scale health data and novel molecular genetic models.
• Havdahl, Alexandra (2018). Undersøke utvikling av psykiske helseproblemer ved bruk av molekylærgenetiske metoder.
• Havdahl, Alexandra; Bishop, Somer L.; Farmer, Cristan; Schjølberg, Synnve; Bresnahan, Michaeline; Hirtz, Deborah; Hornig, Mady; Lord, Catherine; Reichborn-Kjennerud, Ted; Suren, Pål; Øyen, Anne-Siri; Magnus, Per; Susser, Ezra; Lipkin, W. Ian; Stoltenberg, Camilla; Davey Smith, George & Thurm, Audrey (2018). Loss of Social-Communication Skills and Outcomes during Childhood in a Large General Population Cohort.
• Havdahl, Karoline Alexandra & Leppert, Beate (2018). Maternal health behaviours in pregnancy and neurodevelopmental disorders: Evidence of genetic confounding.
• Havdahl, Karoline Alexandra (2017). Best Dissertation Award Talk.
• Havdahl, Karoline Alexandra; Bal, Vanessa Hus; Huerta, Marisela; Pickles, Andrew; Øyen, Anne-Siri; Stoltenberg, Camilla; Lord, Catherine & Bishop, Somer L. (2017). Dr. Havdahl et al. reply. Journal of the American Academy of Child and Adolescent Psychiatry.  ISSN 0890-8567.  56(7), s 619- 620 . doi: 10.1016/j.jaac.2017.05.010
• Havdahl, Karoline Alexandra; Hus Bal, Vanessa; Lord, Catherine; Pickles, Andrew & Bishop, Somer L (2017). In Reply. Journal of the American Academy of Child and Adolescent Psychiatry.  ISSN 0890-8567.  56(4), s 355- 357 . doi: 10.1016/j.jaac.2017.01.018
• Hus Bal, Vanessa; Havdahl, Karoline Alexandra; Bishop, Somer L.; Thurm, Audrey & Farmer, Cristan (2017). The Meaning of SRS-2 Scores is Relative: The Importance of Measurement Invariance in Outcome Measure Selection.
• Havdahl, Karoline Alexandra (2016). Context matters: Factors affecting assessment of autism features.
• Havdahl, Karoline Alexandra (2016). Factors influencing assessment of autism spectrum disorders.
• Havdahl, Karoline Alexandra (2016). Tiltak for å fremme kommunikasjon, læring og sosialt engasjement hos små barn med autisme.
• Havdahl, Karoline Alexandra (2016, 01. mai). Viktig med tidlig oppdagelse av autisme. [Tidsskrift].  Nyhetsbrev Den Norske Mor og Barn Undersøkelsen.
• Havdahl, Karoline Alexandra & Bishop, Somer L. (2016, 01. november). Questions for Bishop, Havdahl: Tantrums trick autism tests. [Internett].  Spectrum (https://spectrumnews.org).
• Havdahl, Karoline Alexandra; Bishop, Somer L.; Farmer, C.; Hus Bal, Vanessa; Robinson, Elise; Sanders, Stephan JK & Thurm, A. (2016). Phenotype-genotype associations in the Simons Simplex Collection for autism spectrum disorder.
• Havdahl, Karoline Alexandra; Bishop, Somer L.; Surén, Pål; Øyen, Anne-Siri; Lord, Catherine; Pickles, Andrew; von Tetzchner, Stephen; Schjølberg, Synnve; Gunnes, Nina; Mady, Hornig; Michaeline, Bresnahan; Lipkin, Ian; Susser, Ezra; Magnus, Per; Stenberg, Nina; Reichborn-Kjennerud, Ted & Stoltenberg, Camilla (2016). Validity of Standardized Diagnostic Instruments for Autism Spectrum Disorders in Toddlers Recruited from a Population-Based Cohort: The Influence of Parental Concern.
• Havdahl, Karoline Alexandra; Hus Bal, Vanessa; Huerta, Marisela; Lord, Catherine & Bishop, Somer L. (2015). Improving the Discriminative Validity of the Social Responsiveness Scale for Autism Spectrum Disorder by Taking Emotional/Behavioral Problems into Account.
• Havdahl, Karoline Alexandra; Huerta, Marisela; Molloy, E. & Bishop, Somer L. (2014). Utility of the Child Behavior Checklist in Differentiating Autism Spectrum Disorders from Other Clinical Disorders.
• Havdahl, Karoline Alexandra (2010). Retningslinjer for utredning av autismespekterforstyrrelser hos voksne (kompendium skrevet på oppdrag fra Distriktspsykiatrisk senter Follo).

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