• Psychoactive substance use disorders in adults with attention deficit hyperactivity disorder (ADHD): effects of ADHD and psychiatric comorbidity

      Biederman, J; Wilens, T; Mick, E; Milberger, S; Spencer, T J; Faraone, Stephen V. (American Psychiatric Association Publishing, 1995-11)
      Objective: The authors evaluated the association between attention deficit hyperactivity disorder (ADHD) and psychoactive substance use disorders in adults with ADHD, attending to comorbidity with mood, anxiety, and antisocial disorders. It was hypothesized that psychiatric comorbidity would be a risk factor for psychoactive substance use disorders. Method: Findings for 120 referred adults with a clinical diagnosis ofchildhood-onset ADHD were compared with those for non-ADHD adult comparison subjects (N=268). All childhood and adult diagnoses were obtained by structured psychiatric interviews for DSM-III-R. Rı ıiiIt.ıi There was a significantly higher lifetime risk for psychoactive substance use disorders in the ADHD adults than in the comparison subjects (52% versus 27%). Although the two groups did not differ in the rate ofalcohol use disorders, the ADHD adults had significantly higher rates ofdrug and drug plus alcohol use disorders than the comparison subjects. ADHD significantly increased the risk for substance use disorders independently ofpsychiatric comorbidity. Antisocial disorders significantly increased the risk for substance use disorders independently ofADHD status. Mood and anxiety disorders increased the risk for substance use disorders in both the ADHD and comparison subjects, but more demonstrably in the comparison subjects. Conclusions: Although psychiatric comorbidity increased the risk for psychoactive substance use disorders in adults with ADHD, by itself ADHD was a significant risk factor for substance use disorders. More information is needed to further delineate risk and protective factors mediating the development of substance use disorders in persons with ADHD.
    • Six-week, double-blind, placebo-controlled study of desipramine for adult attention deficit hyperactivity disorder

      Wilen, T E; Biederman, J; Prince, J; spencer, T J; Faraone, Stephen V.; Warburton, R; Schleifer, D; Harding, M; Linehan, C; Geller, D (American Psychiatric Association Publishing, 1996-09)
      O bjective: The factor structures of individual positive and negative symptoms as well as global ratings were examined in a diagnostically heterogeneous group of subjects. Method: Subjects were identified through a clinical and family study of patients with major psychoses at a VA medical center and evaluated with the Scale for the Assessment of N egative Symptoms and the Scale for the Assessment of Positive Symptoms. For the examination of global-level factor structures (N =630), both principal-component analysis and factor analysis with orthogonal rotation were used. Factor analysis was used for the examination of item-level factor structures as well (N =549). Results: The principal-component analysis of global ratings revealed three factors: negative symptoms, positive symptoms, and disorganization. The factor analysis of global ratings revealed a negative symptom factor and a positive symptom factor. The itemlevel factor analysis revealed two negative symptom factors (diminished expression and disordered relating), two positive symptom factors (bizarre delusions and auditory hallucinations), and a disorganization factor. Conclusions: The generation of additional meaningful factors at the item level suggests that important information about symptoms is lost when only global ratings are viewed. Future work should explore clinical and pathological correlates of the more differentiated item-level symptom dimensions
    • Associations Between ADHD and Psychoactive Substance use Disorders:Findings from a Longitudinal Study of High-Risk Siblings of ADHD Children

      Milberger, Sharon; Biederman, Joseph; Faraone, Stephen V.; Wilens, Timothy; Chu, Monica P. (Wiley, 1997-01)
      The purpose of this study was to determine whether the single nucleotide polymorphisms (SNPs) within candidate genes for attention deficit hyperactivity disorder (ADHD) are associated with the age at onset for ADHD. One hundred and forty-three SNPs were genotyped across five candidate genes (DRD5, SLC6A3, HTR1B, SNAP25, DRD4) for ADHD in 229 families with at least one affected offspring. SNPs with the highest estimated power to detect an association with age at onset were selected for each candidate gene, using a power-based screening procedure that does not compromise the nominal significance level. A time-to-onset analysis for family-based samples was performed on these SNPs to determine if an association exists with age at onset for ADHD. Seven consecutive SNPs surrounding the D5 dopamine receptor gene (DRD5), were associated with the age at onset for ADHD; FDR adjusted q-values ranged from 0.008 to 0.023. This analysis indicates that individuals with the risk genotype develop ADHD earlier than individuals with any other genotype. A haplotype analysis across the 6 significant SNPs that were in linkage disequilibrium with one another, CTCATA, was also found to be significant (p-value = 0.02). We did not observe significant associations with age at onset for the other candidate loci tested. Although definitive conclusions await independent replication, these results suggest that a variant in DRD5 may affect age at onset for ADHD
    • Revisiting the factor structure for positive and negative symptoms: evidence from a large heterogeneous group of psychiatric patients

      Toomey, R; Kremen, W S; simpson, J C; Samson, J A; Seidman, L J; Lynons, M J; Faraone, Stephen V.; Tsuang, M T (American Psychiatric Association Publishing, 1997-03)
      O bjective: The factor structures of individual positive and negative symptoms as well as global ratings were examined in a diagnostically heterogeneous group of subjects. Method: Subjects were identified through a clinical and family study of patients with major psychoses at a VA medical center and evaluated with the Scale for the Assessment of N egative Symptoms and the Scale for the Assessment of Positive Symptoms. For the examination of global-level factor structures (N =630), both principal-component analysis and factor analysis with orthogonal rotation were used. Factor analysis was used for the examination of item-level factor structures as well (N =549). Results: The principal-component analysis of global ratings revealed three factors: negative symptoms, positive symptoms, and disorganization. The factor analysis of global ratings revealed a negative symptom factor and a positive symptom factor. The itemlevel factor analysis revealed two negative symptom factors (diminished expression and disordered relating), two positive symptom factors (bizarre delusions and auditory hallucinations), and a disorganization factor. Conclusions: The generation of additional meaningful factors at the item level suggests that important information about symptoms is lost when only global ratings are viewed. Future work should explore clinical and pathological correlates of the more differentiated item-level symptom dimensions
    • Bipolar and antisocial disorders among relatives of ADHD children: parsing familial subtypes of illness

      Faraone, Stephen V.; Biederman, Joseph; Mennin, Douglas; Russell, Ronald (Wiley, 1998-02-07)
      Attention deficit hyperactivity disorder (ADHD) is a familial disorder that is highly comorbid with conduct disorder and sometimes co-occurs with bipolar disorder. This pattern of comorbidity is also seen among relatives of ADHD probands. A growing literature suggests that ADHD with antisocial comorbidity may be nosologically distinct from other forms of ADHD. A similar pattern has been observed for ADHD and bipolar disorder. Given these results, along with the observed comorbidity between conduct and bipolar disorders, we used data from our study of 140 ADHD and 120 control families to determine if conduct and bipolar disorders in ADHD boys should be considered alternative manifestations of the same familial disorder. The probands and their relatives were examined with DSM-III-R structured diagnostic interviews and were assessed for cognitive, achievement, social, school, and family functioning. Our results provide fairly consistent support for the hypothesis that antisocial- and bipolar-ADHD subtypes are different manifestations of the same familial condition. As predicted by this hypothesis, there was a significant three-way association between variables assessing the family history of each disorder. Moreover, when families were stratified into bipolar, antisocial, and other types, few differences emerged between the bipolar and antisocial families. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 81:108–116, 1998. © 1998 Wiley-Liss, Inc.
    • Effectiveness and Tolerability of Tomoxetine in Adults With Attention Deficit Hyperactivity Disorder

      Spencer, Thomas; Biederman, Joseph; Wilens, Timothy; Prince, Jeffry; Hatch, Mary; Jones, Janice; Harding, Margaret; Faraone, Stephen V.; Seidman, Larry (American Psychiatric Association Publishing, 1998-05)
      Objective: The authors assessed the experimental noradrenergic compound tomoxetine as an alternative treatment for adult attention deficit hyperactivity disorder (ADHD). Method: They conducted a double-blind, placebo-controlled, crossover study of tomoxetine in 22 adults with well-characterized ADHD. Results: Treatment with tomoxetine at an average oral dose of 76 mg/day was well tolerated. Drug-specific improvement in ADHD symptoms was highly significant overall and sufficiently robust to be detectable in a parallel-groups comparison restricted to the first 3 weeks of the protocol. Eleven of 21 patients showed improvement after receiving tomoxetine, compared with only two of 21 patients who improved after receiving placebo. Significant tomoxetine-associated improvement was noted on neuropsychological measures of inhibitory capacity from Stroop tests. Conclusions: This preliminary study showed that tomoxetine was effective in treating adult ADHD and was well tolerated. These promising results provide support for further studies of tomoxetine over an extended period of treatment.
    • Genome-wide search for schizophrenia susceptibility loci: The NIMH genetics initiative and millennium consortium

      Cloninger, C. Robert; Kaufmann, Charles A.; Faraone, Stephen V.; Malaspina, Dolores; Svrakic, Dragan M.; Harkavy-Friedman, Jill; Suarez, Brian K.; Matise, Tara C.; Shore, David; Lee, Hang; et al. (Wiley, 1998-07-10)
      chizophrenia has a complex pattern of inheritance, indicative of interactions among multiple genes and environmental factors. The detection and replication of specific susceptibility loci for such complex disorders are facilitated by the availability of large samples of affected sib pairs and their nuclear families, along with standardized assessment and systematic ascertainment procedures. The NIMH Genetics Initiative on Schizophrenia, a multisite collaborative study, was established as a national resource with a centralized clinical data base and cell repository. The Millennium Schizophrenia Consortium has completed a genome-wide scan to detect susceptibility loci for schizophrenia in 244 individuals from the nuclear families of 92 independent pairs of schizophrenic sibs ascertained by the NIMH Genetics Initiative. The 459 marker loci used in the scan were spaced at 10-cM intervals on average. Individuals of African descent were higher than those of European descent in their average heterozygosity (79% vs. 76%, P < .0001) and number of alleles per marker (9.2 vs. 8.4, P < .0001). Also, the allele frequencies of 73% of the marker loci differed significantly (P < .01) between individuals of European and African ancestry. However, regardless of ethnic background, this sample was largely comprised of schizophrenics with more than a decade of psychosis associated with pervasive social and occupational impairment. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 81:275–281, 1998. © 1998 Wiley-Liss, Inc.
    • Further investigation of a chromosome 15 locus in schizophrenia: Analysis of affected sibpairs from the NIMH genetics initiative

      Leonard, Sherry; Gault, Judith; Moore, Theodore; Hopkins, Jan; Robinson, Misi; Olincy, Ann; Adler, Lawrence E.; Cloninger, C. Robert; Kaufmann, Charles A.; Tsuang, Ming T.; et al. (Wiley, 1998-07-10)
      Linkage of a neurophysiological deficit associated with schizophrenia, i.e., the failure to inhibit the auditory P50 response, was previously reported at chromosome 15q14. The marker with the highest pairwise lod score, D15S1360, was isolated from a yeast artificial chromosome containing a candidate gene, the α7-nicotinic acetylcholine receptor gene. In the present study, this linkage was further investigated in a subset of the NIMH Genetics Initiative schizophrenia families. These families have not been studied neurophysiologically, as were the families in the original report. Therefore, the DSMIII-R diagnosis of schizophrenia was used as the affected phenotype. Twenty families fulfilled the criteria of at least one sibpair concordant for schizophrenia, along with their two parents or another affected relative outside the nuclear family, available for genotyping. Sibpair analysis showed a significant proportion of D15S1360 alleles shared identical-by-descent (0.58; P < 0.0024). The results further support the involvement of this chromosomal locus in the genetic transmission of schizophrenia. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 81:308–312, 1998. © 1998 Wiley-Liss, Inc.
    • NIMH genetics initiative millennium schizophrenia consortium: Linkage analysis of African-American pedigrees

      Kaufmann, Charles A.; Suarez, Brian; Malaspina, Dolores; Pepple, John; Svrakic, Dragan; Markel, Paul D.; Meyer, Joanne; Zambuto, Christopher T.; Schmitt, Karin; Matise, Tara Cox; et al. (Wiley, 1998-07-10)
      The NIMH Genetics Initiative is a multi-site collaborative study designed to create a national resource for genetic studies of complex neuropsychiatric disorders. Schizophrenia pedigrees have been collected at three sites: Washington University, Columbia University, and Harvard University. This article—one in a series that describes the results of a genome-wide scan with 459 short-tandem repeat (STR) markers for susceptibility loci in the NIMH Genetics Initiative schizophrenia sample—presents results for African-American pedigrees. The African-American sample comprises 30 nuclear families and 98 subjects. Seventy-nine of the family members were considered affected by virtue of having received a DSMIII-R diagnosis of schizophrenia (n = 71) or schizoaffective disorder, depressed (n = 8). The families contained a total of 42 independent sib pairs. While no region demonstrated evidence of significant linkage using the criteria suggested by Lander and Kruglyak, several regions, including chromosomes 6q16-6q24, 8pter-8q12, 9q32-9q34, and 15p13-15q12, showed evidence consistent with linkage (P = 0.01–0.05), providing independent support of findings reported in other studies. Moreover, the fact that different genetic loci were identified in this and in the European-American samples, lends credence to the notion that these genetic differences together with differences in environmental exposures may contribute to the reported differences in disease prevalence, severity, comorbidity, and course that has been observed in different racial groups in the United States and elsewhere. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 81:282–289, 1998. © 1998 Wiley-Liss, Inc.
    • Further evidence of an association between maternal smoking during pregnancy and attention deficit hyperactivity disorder: Findings from a high-risk sample of siblings

      Milberger, Sharon; Biederman, Joseph; Faraone, Stephen V.; Jones, Janice (Informa UK Limited, 1998-09)
      The authors investigated the relationship between attentiondeficit/byperactivity disorder (ADHD) and cigarette smoking in siblings of ADHD and non-ADHD probands. They conducted a 4-year follow-up of siblings from ADHD and control-group families. In the siblings of ADHD probands, ADHD was associated with higher rates and earlier onset of cigarette smoking. There was also a significant positive association between cigarette smoking and conduct disorder, major depression, and drug abuse in the siblings, even after adjusting for confounding variables. Moreover, smoking was found to be familial among ADHD families but not control-group families. Our findings indicate that ADHD is a risk factor for early initiation of cigarette smoking in the high-risk siblings of ADHD probands
    • Substance Use Disorders in High-Risk Adolescent Offspring

      Milberger, Stephen V. Faraone, Jose, Sharon (Wiley, 1999-01)
      Objective: To examine the risk for substance use disorders (SUD) in offspring of SUD parents who were not selected due to referral to SUD treatment centers. Method: The original sample was ascertained through two groups of index children: 140 ADHD probands and 120 non-ADHD comparison probands. These groups had 174 and 129 biological siblings and 279 and 240 parents, respectively. Results: We found that: 1) parental SUD was associated with SUD and all SUD subtypes in the offspring; 2) parental alcohol use disorders were associated with alcohol use disorders in the offspring as well as co-occurring alcohol and drug use disorders but not drug use disorders alone in the offspring; and 3) drug use disorders in the parents were associated with drug use disorders but not alcohol use disorders in the offspring. Conclusions: These findings suggest that alcoholism and drug abuse may breed true from parents to their offspring, but further work with larger samples is needed to confirm this idea. Our findings also suggest a possible common diathesis that is expressed as comorbid alcohol and drug use in the offspring of alcoholic parents. If confirmed, these findings may be useful for the development of preventive and early intervention strategies for adolescents at high risk for SUD based on parental history of SUD.
    • The concept of target features in schizophrenia research

      Tsuang, M. T.; Faraone, Stephen V. (Wiley, 1999-05)
      Target features are clinical or neurobiological characteristics that arc expressions of the underlying predisposition to an illness. They comprise a wide range of phenomena, from thc classic signs and symptoms of psychopathology to sophisticated measures of brain structure and function. For schizophrenia, many target features have been identified. These include eye tracking dysfunction, attentional impairment, allusive thinking, neurological signs, thought disorder, characteristic auditory evoked potentials, neuropsychological impairment, structural brain abnormalities and functional brain abnormalities. In their most pathological forms, thcse features are present among many schizophrenic patients, yet it is their presence among their non-psychotic relatives that shows them to be target features. We discuss the theoretical background for target features, present examples and describe how the discovery of target features has implications I for schizophrenia research.
    • Dopamine D4 Gene 7-Repeat Allele and Attention Deficit Hyperactivity Disorder

      Faraone, Stephen V.; Biederman, Joseph; Weiffenbach, Barbara; Keith, Tim; Chu, Monica P.; Weaver, Alix; Spencer, Thomas J.; Wilens, Timothy E.; Frazier, Jean; Cleves, Mario; et al. (American Journal of Psychiatry, 1999-05)
      Objective: Family, twin, and adoption studies show attention deficit hyperactivity disorder (ADHD) to have a substantial genetic component, and some studies have reported an association between ADHD and the dopamine D4 (DRD4) gene. Method: The authors recruited 27 triads that comprised an ADHD adult, his or her spouse, and their ADHD child. These triads were assessed for ADHD, and their DNA was genotyped for DRD4 alleles. Results: A multiallelic transmission disequilibrium test suggested an association between ADHD and the DRD4 7-repeat allele. Among family members, the number of 7-repeat alleles predicted the diagnosis of ADHD. Conclusions: Prior reports of an association between ADHD and DRD4 generalize to families recruited through clinically referred ADHD adults. However, because there are some conflicting studies, further work is needed to clarify the role of DRD4 in the etiology of the disorder.
    • Age-Dependent Decline of Symptoms of Attention Deficit Hyperactivity Disorder: Impact of Remission Definition and Symptom Type

      Biederman, J. (American Psychiatric Association Publishing, 2000-05-01)
      Objective: Symptom decline in attention deficit hyperactivity disorder (ADHD) was examined with different definitions of remission. Method: Symptoms in 128 boys were measured five times over 4 years. The prevalences of syndromatic (less than full syndrome), symptomatic (less than subthreshold diagnosis), and functional (full recovery) remission were estimated as a function of age with multivariate logistic regression. Results: Age was significantly associated with decline in total ADHD symptoms and symptoms of hyperactivity, impulsivity, and inattention. Symptoms of inattention remitted for fewer subjects than did symptoms of hyperactivity or impulsivity. The proportion of subjects experiencing remission varied considerably with the definition used (highest for syndromatic remission, lowest for functional remission). Conclusions: These results indicate that differences in reported remission rates reflect the definition used rather than the disorder’s course. They provide systematic support for the clinical observation that hyperactivity and impulsivity symptoms tend to decline at a higher rate than inattention symptoms.
    • Pediatric mania: a developmental subtype of bipolar disorder?

      Biederman, Joseph; Mick, Eric; Faraone, Stephen V.; Spencer, Thomas; Wilens, Timothy E; Wozniak, Janet (Elsevier BV, 2000-09)
      Despite ongoing controversy, the view that pediatric mania is rare or nonexistent has been increasingly challenged not only by case reports, but also by systematic research. This research strongly suggests that pediatric mania may not be rare but that it may be difficult to diagnose. Since children with mania are likely to become adults with bipolar disorder, the recognition and characterization of childhood-onset mania may help identify a meaningful developmental subtype of bipolar disorder worthy of further investigation. The major difficulties that complicate the diagnosis of pediatric mania include: 1) its pattern of comorbidity may be unique by adult standards, especially its overlap with attention-deficit/hyperactivity disorder, aggression, and conduct disorder; 2) its overlap with substance use disorders; 3) its association with trauma and adversity; and 4) its response to treatment is atypical by adult standards. Biol Psychiatry 2000;48: 458–466 © 2000 Society of Biological Psychiatry.
    • Pediatric mania: a developmental subtype of bipolar disorder?

      Biederman, Joseph; Mick, Eric; Faraone, Stephen V.; Spencer, Thomas; Wilens, Timothy E; Wozniak, Janet (Elsevier BV, 2000-09)
    • A Controlled Study of Behavioral Inhibition in Children of Parents With Panic Disorder and Depression

      Rosenbaum, Jerrold F.; Biederman, Joseph; Hirshfeld-Becker, Dina R.; Kagan, Jerome; Snidman, Nancy; Friedman, Deborah; Nineberg, Allan; Gallery, Daniel J.; Faraone, Stephen V. (American Psychiatric Association Publishing, 2000-12)
      Objective: “Behavioral inhibition to the unfamiliar” has been proposed as a precursor to anxiety disorders. Children with behavioral inhibition are cautious, quiet, introverted, and shy in unfamiliar situations. Several lines of evidence suggest that behavioral inhibition is an index of anxiety proneness. The authors sought to replicate prior findings and examine the specificity of the association between behavioral inhibition and anxiety. Method: Laboratory-based behavioral observations were used to assess behavioral inhibition in 129 young children of parents with panic disorder and major depression, 22 children of parents with panic disorder without major depression, 49 children of parents with major depression without panic disorder, and 84 children of parents without anxiety disorders or major depression (comparison group). A standard definition of behavioral inhibition based on previous research (“dichotomous behavioral inhibition”) was compared with two other definitions. Results: Dichotomous behavioral inhibition was most frequent among the children of parents with panic disorder plus major depression (29% versus 12% in comparison subjects). For all definitions, the univariate effects of parental major depression were significant (conferring a twofold risk for behavioral inhibition), and for most definitions the effects of parental panic disorder conferred a twofold risk as well. Conclusions: These results suggest that the comorbidity of panic disorder and major depression accounts for much of the observed familial link between parental panic disorder and childhood behavioral inhibition. Further work is needed to elucidate the role of parental major depression in conferring risk for behavioral inhibition in children.
    • Report from the second international meeting of the attention deficit hyperactivity disorder Molecular Genetics Network

      Faraone, Stephen V. (Wiley, 2001)
      Given evidence from twin, family, and adoption studies of genetic influence on attention deficit hyperactivity disorder (ADHD), a growing number of researchers have initiated molecular genetics studies to explore the influence of specific genes on this condition. In 1999, these investigators convened to discuss ways of sharing information and facilitating collaborations across research sites. Enthusiastic response to this first conference prompted an even larger group of investigators to come together this year. This recent meeting, held in London, began with a presentation of Hypescheme, an operational criteria checklist developed in an effort to promote the reliable communication of diagnostic and other relevant clinical information related to ADHD. The benefits and limitations of Hypescheme, as well as the continued challenges to collaboration, were discussed. A new ADHD-specific rating scale, developed to be of use in genetic analyses, was also presented. Focus then turned to collaborative projects proposed by investigators and practical suggestions regarding joint data analyses projects. Finally, new data from individual sites were presented. Because the mode of inheritance of ADHD is likely to be complex, efforts to collaborate and cross-validate findings remain an important priority for researchers studying the molecular genetics of this disorder. © 2001 Wiley-Liss, Inc.
    • Patterns of Psychopathology and Dysfunction in High-Risk Children of Parents With Panic Disorder and Major Depression

      Biederman, Joseph; Faraone, Stephen V.; Hirshfeld-Becker, Dina R.; Friedman, Deborah; Robin, Joanna A.; Rosenbaum, Jerrold F. (American Psychiatric Association Publishing, 2001-01)
      Objective: The purpose of the study was to evaluate 1) whether an underlying familial predisposition is shared by all anxiety disorders or whether specific risks are associated with specific disorders, and 2) whether panic disorder and major depression have a familial link. Method: The study compared four groups of children: 1) offspring of parents with panic disorder and comorbid major depression (N=179), 2) offspring of parents with panic disorder without comorbid major depression (N=29), 3) offspring of parents with major depression without comorbid panic disorder (N=59), and 4) offspring of parents with neither panic disorder nor major depression (N=113). Results: Parental panic disorder, regardless of comorbidity with major depression, was associated with an increased risk for panic disorder and agoraphobia in offspring. Parental major depression, regardless of comorbidity with panic disorder, was associated with increased risks for social phobia, major depression, disruptive behavior disorders, and poorer social functioning in offspring. Both parental panic disorder and parental major depression, individually or comorbidly, were associated with increased risk for separation anxiety disorder and multiple (two or more) anxiety disorders in offspring. Conclusions: These findings confirm and extend previous results documenting significant associations between the presence of panic disorder and major depression in parents and patterns of psychopathology and dysfunction in their offspring.
    • Traumatic Brain Injury and Schizophrenia in Members of Schizophrenia and Bipolar Disorder Pedigrees

      Malaspina, Dolores; Goetz, Raymond R.; Friedman, Jill Harkavy; Kaufmann, Charles A.; Faraone, Stephen V.; Tsuang, Ming; Cloninger, C. Robert; Nurnberger, John I.; Blehar, Mary C. (American Psychiatric Association Publishing, 2001-03)
      Objective: Schizophrenia following a traumatic brain injury could be a phenocopy of genetic schizophrenia or the consequence of a gene-environment interaction. Alternatively, traumatic brain injury and schizophrenia could be spuriously associated if those who are predisposed to develop schizophrenia have greater amounts of trauma for other reasons. The authors investigated the relationship between traumatic brain injury and psychiatric diagnoses in a large group of subjects from families with at least two biologically related first-degree relatives with schizophrenia, schizoaffective disorder, or bipolar disorder. Method: The Diagnostic Interview for Genetic Studies was used to determine history of traumatic brain injury and diagnosis for 1,275 members of multiplex bipolar disorder pedigrees and 565 members of multiplex schizophrenia pedigrees. Results: Rates of traumatic brain injury were significantly higher for those with a diagnosis of schizophrenia, bipolar disorder, and depression than for those with no mental illness. However, multivariate analysis of within-pedigree data showed that mental illness was related to traumatic brain injury only in the schizophrenia pedigrees. Independent of diagnoses, family members of those with schizophrenia were more likely to have had traumatic brain injury than were members of the bipolar disorder pedigrees. The members of the schizophrenia pedigrees also failed to show the gender difference for traumatic brain injury (more common in men than in women) that was expected and was present in the bipolar disorder pedigrees. Subjects with a schizophrenia diagnosis who were members of the bipolar disorder pedigrees (and thus had less genetic vulnerability to schizophrenia) were less likely to have had traumatic brain injury (4.5%) than were subjects with schizophrenia who were members of the schizophrenia pedigrees (and who had greater genetic vulnerability to schizophrenia) (19.6%). Conclusions: Members of the schizophrenia pedigrees, even those without a schizophrenia diagnosis, had greater exposure to traumatic brain injury compared to members of the bipolar disorder pedigrees. Within the schizophrenia pedigrees, traumatic brain injury was associated with a greater risk of schizophrenia, consistent with synergistic effects between genetic vulnerability for schizophrenia and traumatic brain injury. Posttraumatic-braininjury schizophrenia in multiplex schizophrenia pedigrees does not appear to be a phenocopy of the genetic disorder.