In: Twin research and human genetics: the official journal of the International Society for Twin Studies (ISTS) and the Human Genetics Society of Australasia, Band 11, Heft 2, S. 240-241
AbstractTo raise twins is a challenge, just as it is to be part of a twin pair. This was the message communicated by Joan Friedman, the author of the book: Emotionally Healthy Twins: A New Philosophy for Parenting Two Unique Individuals. Friedman is a twin herself and also a mother of twins, and a psychotherapist specialized in the treatment of twin-related problems. The book presents seven basic concepts meant to raise twins in such a way that they become emotionally healthy adults.
In: Twin research and human genetics: the official journal of the International Society for Twin Studies (ISTS) and the Human Genetics Society of Australasia, Band 8, Heft 3, S. 224-231
AbstractTwin studies that examine the effect of specific environmental risk factors on psychiatric disorders assume that there are no differences in prevalences of these risk factors between twins and singletons. Violation of this assumption signifies that the results from twin studies might not generalize to singletons. Another assumption, not only often underlying twin studies but also epidemiological research, is that life- events are not influenced by familial factors. We tested differences in prevalences of experienced life events in a Dutch sample of 2086 monozygotic (MZ) twins, 2090 dizygotic (DZ) twins and 1307 of their siblings. Self-reported data on life events (illness of self, illness of a significant other, spouse/romantic relationship, divorce/break-up of a relationship, death of a significant other, traffic accident, robbery, violent assault, sexual assault) were available from a survey- study. We further investigated whether familial resemblance was present for the exposure to these life events and, if so, whether this resemblance was due to genetic or common environmental factors. No differences were found in the prevalences of life events between MZ twins, DZ twins and their siblings. There was evidence for familial aggregation of all life events, except for traffic accidents in women. Results indicated genetic control on the presence of a spouse or involvement in a relationship. Familial resemblance of illness and death of a significant other was mainly due to common environment. For the other life events, it was not possible to distinguish between genetic and common environmental effects.
In: Twin research and human genetics: the official journal of the International Society for Twin Studies (ISTS) and the Human Genetics Society of Australasia, Band 18, Heft 1, S. 52-60
This study investigates the relative contribution of genetic and environmental factors to the stability of obsessive-compulsive (OC) symptoms in an adult population-based sample. We collected data from twin pairs and their siblings, using the Padua Inventory Revised Abbreviated, from the population-based Netherlands Twin Register (NTR) in 2002 (n= 10.134) and 2008 (n= 15.720). Multivariate twin analyses were used to estimate the stability of OC symptoms as a function of genetic and environmental components. OC symptoms were found to be highly stable, with a longitudinal phenotypic correlation of 0.63. Longitudinal broad sense heritability was found to be 56.0%. Longitudinal correlations for genetic (r= 0.58 for additive,r= 1 for non-additive genetic factors) and non-shared environment (r= 0.46) reflected stable effects, indicating that both genes and environment are influencing the stability of OC symptoms in adults. For the first time, evidence is reported for non-additive genetic effects on the stability of OC symptoms. In conclusion, this study showed that OC symptoms are highly stable across time in adults, and that genetic effects contribute mostly to this stability, both in an additive and non-additive way, besides non-shared environmental factors. These data are informative with respect to adult sample selection for future genetic studies, and suggest that gene–gene interaction studies are needed to further understand the dominance effect found in this study.
In: Twin research and human genetics: the official journal of the International Society for Twin Studies (ISTS) and the Human Genetics Society of Australasia, Band 15, Heft 3, S. 372-383
One of the core behavioral features associated with obsessive compulsive symptomatology is the inability to inhibit thoughts and/or behaviors. Neuroimaging studies have indicated abnormalities in frontostriatal and dorsolateral prefrontal – anterior cingulate circuits during inhibitory control in patients with obsessive compulsive disorder compared with controls. In the present study, task performance and brain activation during Stroop color-word and Flanker interference were compared within monozygotic twin pairs discordant for obsessive compulsive symptoms and between groups of pairs scoring very low or very high on obsessive compulsive symptoms, in order to examine the differential impact of non-shared environmental versus genetic risk factors for obsessive compulsive symptomatology on inhibitory control related functional brain activation. Although performance was intact, brain activation during inhibition of distracting information differed between obsessive compulsive symptom high-scoring compared to low-scoring subjects. Regions affected in the discordant group (e.g., temporal and anterior cingulate gyrus) were partly different from those observed to be affected in the concordant groups (e.g., parietal gyrus and thalamus). A robust increase in dorsolateral prefrontal activity during response interference was observed in both the high-scoring twins of the discordant sample and the high-scoring twins of the concordant sample, marking this structure as a possible key region for disturbances in inhibitory control in obsessive compulsive disorder.
In: Twin research and human genetics: the official journal of the International Society for Twin Studies (ISTS) and the Human Genetics Society of Australasia, Band 18, Heft 6, S. 699-709
Tic disorders are moderately heritable common psychiatric disorders that can be highly troubling, both in childhood and in adulthood. In this study, we report results obtained in the first epigenome-wide association study (EWAS) of tic disorders. The subjects are participants in surveys at the Netherlands Twin Register (NTR) and the NTR biobank project. Tic disorders were measured with a self-report version of the Yale Global Tic Severity Scale Abbreviated version (YGTSS-ABBR), included in the 8th wave NTR data collection (2008). DNA methylation data consisted of 411,169 autosomal methylation sites assessed by the Illumina Infinium HumanMethylation450 BeadChip Kit (HM450k array). Phenotype and DNA methylation data were available in 1,678 subjects (mean age = 41.5). No probes reached genome-wide significance (p < 1.2 × 10−7). The strongest associated probe was cg15583738, located in an intergenic region on chromosome 8 (p = 1.98 × 10−6). Several of the top ranking probes (p < 1 × 10−4) were in or nearby genes previously associated with neurological disorders (e.g., GABBRI, BLM, and ADAM10), warranting their further investigation in relation to tic disorders. The top significantly enriched gene ontology (GO) terms among higher ranking methylation sites included anatomical structure morphogenesis (GO:0009653, p = 4.6 × 10−15) developmental process (GO:0032502, p = 2.96 × 10−12), and cellular developmental process (GO:0048869, p = 1.96 × 10−12). Overall, these results provide a first insight into the epigenetic mechanisms of tic disorders. This first study assesses the role of DNA methylation in tic disorders, and it lays the foundations for future work aiming to unravel the biological mechanisms underlying the architecture of this disorder.
In: Twin research and human genetics: the official journal of the International Society for Twin Studies (ISTS) and the Human Genetics Society of Australasia, Band 8, Heft 6, S. 609-615
The direct estimation of heritability from genome-wide common variant data as implemented in the program Genome-wide Complex Trait Analysis (GCTA) has provided a means to quantify heritability attributable to all interrogated variants. We have quantified the variance in liability to disease explained by all SNPs for two phenotypically-related neurobehavioral disorders, obsessive-compulsive disorder (OCD) and Tourette Syndrome (TS), using GCTA. Our analysis yielded a heritability point estimate of 0.58 (se = 0.09, p = 5.64e-12) for TS, and 0.37 (se = 0.07, p = 1.5e-07) for OCD. in addition, we conducted multiple genomic partitioning analyses to identify genomic elements that concentrate this heritability. We examined genomic architectures of TS and OCD by chromosome, MAF bin, and functional annotations. in addition, we assessed heritability for early onset and adult onset OCD. Among other notable results, we found that SNPs with a minor allele frequency of less than 5% accounted for 21% of the TS heritability and 0% of the OCD heritability. Additionally, we identified a significant contribution to TS and OCD heritability by variants significantly associated with gene expression in two regions of the brain (parietal cortex and cerebellum) for which we had available expression quantitative trait loci (eQTLs). Finally we analyzed the genetic correlation between TS and OCD, revealing a genetic correlation of 0.41 (se = 0.15, p = 0.002). These results are very close to previous heritability estimates for TS and OCD based on twin and family studies, suggesting that very little, if any, heritability is truly missing (i.e., unassayed) from TS and OCD GWAS studies of common variation. the results also indicate that there is some genetic overlap between these two phenotypically-related neuropsychiatric disorders, but suggest that the two disorders have distinct genetic architectures. ; Judah Foundation ; NIH ; Tourette Syndrome Association International Consortium for Genetics (TSAICG) ; New Jersey Center for Tourette Syndrome and Associated Disorders ; NIMH ; Obsessive Compulsive Foundation ; Ontario Mental Health Foundation ; Tourette Syndrome Association ; American Academy of Child and Adolescent Psychiatry (AACAP) ; Anxiety Disorders Association of America (ADAA) ; University of British Columbia ; Michael Smith Foundation ; American Recovery and Re-investment Act (ARRA) ; Australian Research Council ; Australian National Health and Medical Research Council ; German Research Foundation ; NIH Genes, Environment and Health Initiative [GEI] ; Gene Environment Association Studies (GENEVA) under GEI ; NIH GEI ; National Institute on Alcohol Abuse and Alcoholism ; National Institute on Drug Abuse ; Univ Chicago, Dept Med, Med Genet Sect, Chicago, IL 60637 USA ; Harvard Univ, Massachusetts Gen Hosp, Dept Psychiat,Sch Med, Psychiat & Neurodev Genet Unit,Ctr Human Genet Re, Boston, MA USA ; Broad Inst Harvard & MIT, Stanley Ctr Psychiat Res, Cambridge, MA USA ; Univ Chicago, Dept Med, Chicago, IL 60637 USA ; Univ Chicago, Dept Human Genet, Chicago, IL 60637 USA ; Univ Amsterdam, Acad Med Ctr, Dept Psychiat, NL-1105 AZ Amsterdam, Netherlands ; Massachusetts Gen Hosp, Analyt & Translat Genet Unit, Boston, MA 02114 USA ; Univ Queensland, Diamantina Inst, Brisbane, Qld 4072, Australia ; Univ Queensland, Queensland Brain Inst, Brisbane, Qld 4072, Australia ; Univ Hlth Network, Toronto Western Res Inst, Toronto, ON, Canada ; Hosp Sick Children, Toronto, ON M5G 1X8, Canada ; Univ Vita Salute San Raffaele, Milan, Italy ; Hadassah Hebrew Univ Med Ctr, Herman Dana Div Child & Adolescent Psychiat, Jerusalem, Israel ; Univ Pontificia Bolivariana, Univ Antioquia, Medellin, Colombia ; Johns Hopkins Univ, Sch Med, Dept Psychiat & Behav Sci, Baltimore, MD 21205 USA ; Yale Univ, Dept Psychiat, New Haven, CT 06520 USA ; Yale Univ, Sch Med, Ctr Child Study, New Haven, CT 06510 USA ; North Shore Long Isl Jewish Med Ctr, Manhasset, NY USA ; NYU Med Ctr, New York, NY 10016 USA ; North Shore Long Isl Jewish Hlth Syst, Manhasset, NY USA ; Hofstra Univ, Sch Med, Hempstead, NY 11550 USA ; Inst Nacl Psiquiatria Ramon de la Fuente Muniz, Mexico City, DF, Mexico ; UCL, London, England ; Univ Hong Kong, Dept Psychiat, Hong Kong, Hong Kong, Peoples R China ; Univ São Paulo, Sch Med, Dept Psychiat, São Paulo, Brazil ; Vrije Univ Amsterdam, Med Ctr, Dept Psychiat, Amsterdam, Netherlands ; Univ Utrecht, Dept Clin & Hlth Psychol, Utrecht, Netherlands ; Altrecht Acad Anxiety Ctr, Utrecht, Netherlands ; Univ Milan, Osped San Raffaele, I-20127 Milan, Italy ; Univ Calif Los Angeles, Dept Psychol, Los Angeles, CA 90024 USA ; Univ Calif San Diego, Dept Psychiat, La Jolla, CA 92093 USA ; Univ Montreal, Montreal, PQ, Canada ; Univ Calif Los Angeles, Keck Sch Med, Div Biostat, Dept Preventat Med, Los Angeles, CA USA ; Univ Illinois, Dept Psychiat, Inst Juvenile Res, Chicago, IL 60612 USA ; Univ Ghent, Lab Pharmaceut Biotechnol, B-9000 Ghent, Belgium ; Inst Pasteur, Paris, France ; French Natl Sci Fdn, Fondat Fondamental, Creteil, France ; Hop Robert Debre, AP HP, Dept Child & Adolescent Psychiat, F-75019 Paris, France ; Univ Montreal, Dept Psychiat, Montreal, PQ H3C 3J7, Canada ; Univ Wurzburg, Dept Child & Adolescent Psychiat Psychosomat & Ps, D-97070 Wurzburg, Germany ; Univ Munich, Dept Psychiat & Psychotherapy, Munich, Germany ; Yale Univ, Sch Med, Dept Psychiat, New Haven, CT USA ; Harvard Univ, Sch Med, Dept Psychiat, Massachusetts Gen Hosp,OCD Program, Boston, MA 02115 USA ; Univ Med Greifswald, Helios Hosp Stralsund, Dept Psychiat & Psychotherapy, Greifswald, Germany ; Butler Hosp, Brown Med Sch, Dept Psychiat & Human Behav, Providence, RI 02906 USA ; Shaare Zedek Med Ctr, Neuropediatr Unit, Jerusalem, Israel ; Rutgers State Univ, Dept Genet, Human Genet Inst New Jersey, Piscataway, NJ USA ; Univ Stellenbosch, Dept Psychiat, ZA-7600 Stellenbosch, South Africa ; Univ São Paulo, Fac Med, Dept Psychiat, BR-05508 São Paulo, Brazil ; Baylor Coll Med, Dept Neurol, Parkinsons Dis Ctr, Houston, TX 77030 USA ; Baylor Coll Med, Dept Neurol, Movement Disorders Clin, Houston, TX 77030 USA ; Massachusetts Gen Hosp, Dept Psychiat, Boston, MA 02114 USA ; Ctr Addict & Mental Hlth, Neurogenet Sect, Toronto, ON, Canada ; Univ Toronto, Dept Psychiat, Toronto, ON, Canada ; Yale Univ, Sch Med, Dept Genet, Yale Child Study Ctr, New Haven, CT 06510 USA ; Overlook Hosp, Atlantic Neurosci Inst, Summit, NJ USA ; Carracci Med Grp, Mexico City, DF, Mexico ; Inst Mondor Rech Biomed, Creteil, France ; Yale Univ, Ctr Child Study, New Haven, CT 06520 USA ; Univ Bonn, Dept Psychiat & Psychotherapy, Bonn, Germany ; Univ Illinois, Dept Psychiat, Inst Human Genet, Chicago, IL 60612 USA ; Univ Stellenbosch, Dept Psychiat, MRC Unit Anxiety & Stress Disorders, ZA-7600 Stellenbosch, South Africa ; Univ Calif San Francisco, Dept Psychiat, San Francisco, CA USA ; UCI, Sch Med, Dept Psychiat & Human Behav, Irvine, CA USA ; Univ Utah, Salt Lake City, UT USA ; NIMH Intramural Res Program, Clin Sci Lab, Bethesda, MD USA ; Med City Dallas Hosp, Dept Clin Res, Dallas, TX USA ; Univ Med Ctr, Rudolf Magnus Inst Neurosci, Dept Psychiat, Utrecht, Netherlands ; Univ Calif Los Angeles, Semel Inst Neurosci & Human Behav, Ctr Neurobehav Genet, Los Angeles, CA 90024 USA ; Yale Univ, Sch Med, Dept Genet, New Haven, CT 06510 USA ; Univ So Calif, Keck Sch Med, Zilkha Neurogenet Inst, Dept Psychiat & Behav Sci, Los Angeles, CA 90033 USA ; Univ Calif Los Angeles, David Geffen Sch Med, Dept Psychiat & Biobehav Sci, Los Angeles, CA 90095 USA ; Yale Univ, Dept Psychol, New Haven, CT 06520 USA ; Partners Psychiat & McLean Hosp, Boston, MA USA ; Sunnybrook Hlth Sci Ctr, Frederick W Thompson Anxiety Disorders Ctr, Toronto, ON M4N 3M5, Canada ; St George Hosp, London, England ; Sch Med, London, England ; Hosp Nacl Ninos Dr Carlos Saenz Herrera, San Jose, Costa Rica ; Universidade Federal de São Paulo, Dept Psychiat, Child & Adolescent Psychiat Unit UPIA, São Paulo, Brazil ; Wayne State Univ, Dept Psychiat & Behav Neurosci, Detroit, MI 48207 USA ; Detroit Med Ctr, Detroit, MI USA ; McGill Univ, Montreal Neurol Inst, Montreal, PQ, Canada ; Univ Cologne, Dept Psychiat & Psychotherapy, D-50931 Cologne, Germany ; Univ Fed Bahia, Univ Hlth Care Serv SMURB, Salvador, BA, Brazil ; Youthdale Treatment Ctr, Toronto, ON, Canada ; Johns Hopkins Univ Sch Med, Baltimore, MD USA ; Univ Cape Town, ZA-7925 Cape Town, South Africa ; Univ Med Ctr Utrecht, Dept Med Genet, Utrecht, Netherlands ; Vanderbilt Univ, Kennedy Ctr Res Human Dev, Dept Psychiat, Nashville, TN 37235 USA ; Vanderbilt Univ, Kennedy Ctr Res Human Dev, Dept Pediat & Pharmacol, Nashville, TN 37235 USA ; Vanderbilt Univ, Inst Brain, Nashville, TN 37235 USA ; Univ Zurich, Dept Child & Adolescent Psychiat, Zurich, Switzerland ; Univ Wurzburg, Dept Child & Adolescent Psychiat, D-97070 Wurzburg, Germany ; Univ Amsterdam, Acad Med Ctr, Ctr Psychiat, NL-1105 BC Amsterdam, Netherlands ; Inst Royal Netherlands Acad Arts & Sci NIN KNAW, Netherlands Inst Neurosci, Amsterdam, Netherlands ; NIMH Intramural Res Program, Unit Stat Genom, Bethesda, MD USA ; Univ Utah, Dept Psychiat, Salt Lake City, UT USA ; Natl Inst Genom Med SAP, Carracci Med Grp, Mexico City, DF, Mexico ; Vrije Univ Amsterdam, Ctr Neurogen & Cognit Res, Dept Funct Genom, Amsterdam, Netherlands ; Vrije Univ Amsterdam Med Ctr, Dept Clin Genet, Amsterdam, Netherlands ; Erasmus Univ, Med Ctr, Dept Child & Adolescent Psychiat, Rotterdam, Netherlands ; Univ Michigan, Dept Psychiat, Ann Arbor, MI 48109 USA ; Vrije Univ Amsterdam, Med Ctr, Dept Clin Genet, Sect Med Genom, Amsterdam, Netherlands ; German Ctr Neurodegenerat Dis, Tubingen, Germany ; Hosp Sick Children, Program Genet & Genome Biol, Toronto, ON M5G 1X8, Canada ; Erasmus MC, Dept Clin Genet, Rotterdam, Netherlands ; Univ British Columbia, British Columbia Mental Hlth & Addict Res Inst, Vancouver, BC V5Z 1M9, Canada ; Brigham & Womens Hosp, Div Cognit & Behav Neurol, Boston, MA 02115 USA ; Massachusetts Gen Hosp, Dept Neurol, Boston, MA 02114 USA ; Universidade Federal de São Paulo, Dept Psychiat, Child & Adolescent Psychiat Unit UPIA, São Paulo, Brazil ; NIH: NS40024 ; NIH: NS16648 ; NIH: MH079489 ; NIH: MH073250 ; NIH: NS037484 ; NIH: 1R01MH079487-01A1 ; NIH: K20 MH01065 ; NIH: R01 MH58376 ; NIH: MH085057 ; NIH: MH079494 ; NIH: HHSN268200782096C ; NIMH: R01MH092293 ; American Recovery and Re-investment Act (ARRA): NS40024-07S1 ; American Recovery and Re-investment Act (ARRA): NS16648-29S1 ; Australian Research Council: FT0991360 ; Australian Research Council: DE130100614 ; Australian National Health and Medical Research Council: 1047956 ; Australian National Health and Medical Research Council: 1052684 ; German Research Foundation: DFG GR 1912/1-1 ; NIH Genes, Environment and Health Initiative [GEI]: U01 HG004422 ; NIH GEI: U01HG004438 ; : R01 MH090937 ; : P50MH094267 ; Web of Science