Amish Study, II: Consensus diagnoses and reliability results

The Cultural and Religious Complexities of Amish-Focused Mental Health Conditions Research: Insights from an Exhaustive Narrative Review and Case Study of Counseling Controversies

Mental health conditions research often relies on reductionist cultural assumptions about the population studied and instruments validated from majority populations. In exhaustively reviewing the limited body of Amish mental health conditions research, we find that studies are well-executed by methodological protocols but that findings are inconsistent or limited in generalizability, instrument validity remains contested, and study investigation into Amish cultural and religious dynamics is limited. A case study from a sizeable Amish community in Ohio illustrates how various ideologies-notably old Amish religious theology, the scientific-psychological, and the Evangelical Protestant-have generated population-internal controversies among the Amish over defining and treating mental health conditions, suggesting that mental health conditions research and diagnosis of ethnic religious adherents should better account for internal cultural-religious dynamics. In order to make some assertions about how Amish culture and religion impacts mental health conditions, future research should include pre-study investigations into the targeted population's cultural and religious dynamics, consist of more nuanced case reports from therapists and psychiatrists, and include replication studies at different times and places, with deliberate attention to contextual factors.

Clinical and genetic validity of quantitative bipolarity

Research has yet to provide a comprehensive understanding of the genetic basis of bipolar disorder (BP). In genetic studies, defining the phenotype by diagnosis may miss risk-allele carriers without BP. The authors aimed to test whether quantitatively detected subclinical symptoms of bipolarity identifies a heritable trait that infers risk for BP. The Quantitative Bipolarity Scale (QBS) was administered to 310 Old Order Amish or Mennonite individuals from multigenerational pedigrees; 110 individuals had psychiatric diagnoses (20 BP, 61 major depressive disorders (MDD), 3 psychotic disorders, 26 other psychiatric disorders). Familial aggregation of QBS was calculated using the variance components method to derive heritability and shared household effects. The QBS score was significantly higher in BP subjects (31.5 ± 3.6) compared to MDD (16.7 ± 2.0), other psychiatric diagnoses (7.0 ± 1.9), and no psychiatric diagnosis (6.0 ± 0.65) (all p < 0.001). QBS in the whole sample was significantly heritable (h² = 0.46 ± 0.15, p < 0.001) while the variance attributed to the shared household effect was not significant (p = 0.073). When subjects with psychiatric illness were removed, the QBS heritability was similar (h² = 0.59 ± 0.18, p < 0.001). These findings suggest that quantitative bipolarity as measured by QBS can separate BP from other psychiatric illnesses yet is significantly heritable with and without BP included in the pedigrees suggesting that the quantitative bipolarity describes a continuous heritable trait that is not driven by a discrete psychiatric diagnosis. Bipolarity trait assessment may be used to supplement the diagnosis of BP in future genetic studies and could be especially useful for capturing subclinical genetic contributions to a BP phenotype.

Genetic pleiotropy between mood disorders, metabolic, and endocrine traits in a multigenerational pedigree

Bipolar disorder (BD) is a mental disorder characterized by alternating periods of depression and mania. Individuals with BD have higher levels of early mortality than the general population, and a substantial proportion of this is due to increased risk for comorbid diseases. To identify the molecular events that underlie BD and related medical comorbidities, we generated imputed whole-genome sequence data using a population-specific reference panel for an extended multigenerational Old Order Amish pedigree (n = 394), segregating BD and related disorders. First, we investigated all putative disease-causing variants at known Mendelian disease loci present in this pedigree. Second, we performed genomic profiling using polygenic risk scores (PRS) to establish each individual's risk for several complex diseases. We identified a set of Mendelian variants that co-occur in individuals with BD more frequently than their unaffected family members, including the R3527Q mutation in APOB associated with hypercholesterolemia. Using PRS, we demonstrated that BD individuals from this pedigree were enriched for the same common risk alleles for BD as the general population (β = 0.416, p = 6 × 10^-4). Furthermore, we find evidence for a common genetic etiology between BD risk and polygenic risk for clinical autoimmune thyroid disease (p = 1 × 10^-4), diabetes (p = 1 × 10^-3), and lipid traits such as triglyceride levels (p = 3 × 10^-4) in the pedigree. We identify genomic regions that contribute to the differences between BD individuals and unaffected family members by calculating local genetic risk for independent LD blocks. Our findings provide evidence for the extensive genetic pleiotropy that can drive epidemiological findings of comorbidities between diseases and other complex traits.

The International College of Neuropsychopharmacology (CINP) Treatment Guidelines for Bipolar Disorder in Adults (CINP-BD-2017), Part 1: Background and Methods of the Development of Guidelines

BACKGROUND

This paper includes a short description of the important clinical aspects of Bipolar Disorder with emphasis on issues that are important for the therapeutic considerations, including mixed and psychotic features, predominant polarity, and rapid cycling as well as comorbidity.

METHODS

The workgroup performed a review and critical analysis of the literature concerning grading methods and methods for the development of guidelines.

RESULTS

The workgroup arrived at a consensus to base the development of the guideline on randomized controlled trials and related meta-analyses alone in order to follow a strict evidence-based approach. A critical analysis of the existing methods for the grading of treatment options was followed by the development of a new grading method to arrive at efficacy and recommendation levels after the analysis of 32 distinct scenarios of available data for a given treatment option.

CONCLUSION

The current paper reports details on the design, method, and process for the development of CINP guidelines for the treatment of Bipolar Disorder. The rationale and the method with which all data and opinions are combined in order to produce an evidence-based operationalized but also user-friendly guideline and a specific algorithm are described in detail in this paper.

Symptom profiles and illness course among Anabaptist and Non-Anabaptist adults with major mood disorders

Background

Anabaptists comprise large and growing Amish and Mennonite populations with a unique genetic heritage and cultural background. Little is known about the symptoms and course of major mood disorders in Anabaptists. Even less is known about the impact of potential moderators on symptom severity and course.

Methods

A sample of Amish and Mennonite participants with bipolar, recurrent unipolar, or schizoaffective bipolar disorder (n = 155) were systematically evaluated with a well-validated instrument. Cases were compared with non-Anabaptist participants (n = 155) matched for age, sex, and psychiatric diagnosis and evaluated by the same methods.

Results

Despite substantial cultural differences, the profile of manic and depressive symptoms during illness episodes did not significantly differ between the two groups. Alcohol use disorder (AUD) was significantly less frequent among Anabaptists, and was associated with more major depressive episodes and more hospitalizations for major depression in Anabaptist, but not non-Anabaptist participants. Lifetime history of head injury showed a trend toward association with more episodes of major depression in both Anabaptist and non-Anabaptist groups that did not withstand multiple test correction.

Conclusions

The presentation of a highly heritable psychiatric illness such as bipolar disorder does not differ in cases drawn from genetically unique Anabaptist populations. However, alcohol comorbidity, head injury, and their effects on illness course suggest some differences that deserve further investigation.

Test-retest reliability of schizoaffective disorder compared with schizophrenia, bipolar disorder, and unipolar depression--a systematic review and meta-analysis

OBJECTIVES

Schizoaffective disorder is a frequent diagnosis, and its reliability is subject to ongoing discussion. We compared the diagnostic reliability of schizoaffective disorder with its main differential diagnoses.

METHODS

We systematically searched Medline, Embase, and PsycInfo for all studies on the test-retest reliability of the diagnosis of schizoaffective disorder as compared with schizophrenia, bipolar disorder, and unipolar depression. We used meta-analytic methods to describe and compare Cohen's kappa as well as positive and negative agreement. In addition, multiple pre-specified and post hoc subgroup and sensitivity analyses were carried out.

RESULTS

Out of 4,415 studies screened, 49 studies were included. Test-retest reliability of schizoaffective disorder was consistently lower than that of schizophrenia (in 39 out of 42 studies), bipolar disorder (27/33), and unipolar depression (29/35). The mean difference in kappa between schizoaffective disorder and the other diagnoses was approximately 0.2, and mean Cohen's kappa for schizoaffective disorder was 0.50 (95% confidence interval: 0.40-0.59). While findings were unequivocal and homogeneous for schizoaffective disorder's diagnostic reliability relative to its three main differential diagnoses (dichotomous: smaller versus larger), heterogeneity was substantial for continuous measures, even after subgroup and sensitivity analyses.

CONCLUSIONS

In clinical practice and research, schizoaffective disorder's comparatively low diagnostic reliability should lead to increased efforts to correctly diagnose the disorder.

Disruption of sonic hedgehog signaling in Ellis-van Creveld dwarfism confers protection against bipolar affective disorder

Ellis-van Creveld syndrome, an autosomal recessively inherited chondrodysplastic dwarfism, is frequent among Old Order Amish of Pennsylvania. Decades of longitudinal research on bipolar affective disorder (BPAD) revealed cosegregation of high numbers of EvC and Bipolar I (BPI) cases in several large Amish families descending from the same pioneer. Despite the high prevalence of both disorders in these families, no EvC individual has ever been reported with BPI. The proximity of the EVC gene to our previously reported chromosome 4p16 BPAD locus with protective alleles, coupled with detailed clinical observations that EvC and BPI do not occur in the same individuals, led us to hypothesize that the genetic defect causing EvC in the Amish confers protection from BPI. This hypothesis is supported by a significant negative association of these two disorders when contrasted with absence of disease (P=0.029, Fisher's exact test, two-sided, verified by permutation to estimate the null distribution of the test statistic). As homozygous Amish EVC mutations causing EvC dwarfism do so by disrupting sonic hedgehog (Shh) signaling, our data implicate Shh signaling in the underlying pathophysiology of BPAD. Understanding how disrupted Shh signaling protects against BPI could uncover variants in the Shh pathway that cause or increase risk for this and related mood disorders.

Copy number variants encompassing Mendelian disease genes in a large multigenerational family segregating bipolar disorder

BACKGROUND

Bipolar affective disorder (BP) is a common, highly heritable psychiatric disorder characterized by periods of depression and mania. Using dense SNP genotype data, we characterized CNVs in 388 members of an Old Order Amish Pedigree with bipolar disorder. We identified CNV regions arising from common ancestral mutations by utilizing the pedigree information. By combining this analysis with whole genome sequence data in the same individuals, we also explored the role of compound heterozygosity.

RESULTS

Here we describe 541 inherited CNV regions, of which 268 are rare in a control population of European origin but present in a large number of Amish individuals. In addition, we highlight a set of CNVs found at higher frequencies in BP individuals, and within genes known to play a role in human development and disease. As in prior reports, we find no evidence for an increased burden of CNVs in BP individuals, but we report a trend towards a higher burden of CNVs in known Mendelian disease loci in bipolar individuals (BPI and BPII, p = 0.06).

CONCLUSIONS

We conclude that CNVs may be contributing factors in the phenotypic presentation of mood disorders and co-morbid medical conditions in this family. These results reinforce the hypothesis of a complex genetic architecture underlying BP disorder, and suggest that the role of CNVs should continue to be investigated in BP data sets.

Genomic view of bipolar disorder revealed by whole genome sequencing in a genetic isolate

Bipolar disorder is a common, heritable mental illness characterized by recurrent episodes of mania and depression. Despite considerable effort to elucidate the genetic underpinnings of bipolar disorder, causative genetic risk factors remain elusive. We conducted a comprehensive genomic analysis of bipolar disorder in a large Old Order Amish pedigree. Microsatellite genotypes and high-density SNP-array genotypes of 388 family members were combined with whole genome sequence data for 50 of these subjects, comprising 18 parent-child trios. This study design permitted evaluation of candidate variants within the context of haplotype structure by resolving the phase in sequenced parent-child trios and by imputation of variants into multiple unsequenced siblings. Non-parametric and parametric linkage analysis of the entire pedigree as well as on smaller clusters of families identified several nominally significant linkage peaks, each of which included dozens of predicted deleterious variants. Close inspection of exonic and regulatory variants in genes under the linkage peaks using family-based association tests revealed additional credible candidate genes for functional studies and further replication in population-based cohorts. However, despite the in-depth genomic characterization of this unique, large and multigenerational pedigree from a genetic isolate, there was no convergence of evidence implicating a particular set of risk loci or common pathways. The striking haplotype and locus heterogeneity we observed has profound implications for the design of studies of bipolar and other related disorders.

Bipolar disorder is a common, heritable mental illness characterized by recurrent episodes of mania and depression. Despite considerable efforts genetic studies have yet to reveal the precise genetic underpinnings of the disorder. In this study we have analyzed a large extended pedigree of Old Order Amish that segregates bipolar disorder. Our study design integrates both dense genotype and whole-genome sequence data. In a combined linkage and association analysis we identify five chromosomal regions with nominally significant or suggestive evidence for linkage, several of which constitute replication of earlier linkage findings for bipolar disorder in non-Amish families. Association analysis of genetic variants in each of the linkage regions yielded a number of plausible candidate genes for bipolar disorder. The striking genetic heterogeneity we observed in this genetic isolate has profound implications for the study of bipolar disorder in the general population.

A 16-year prospective study of prodromal features prior to BPI onset in well Amish children

BACKGROUND

Longitudinal research of well Amish children over 16 years to identify the pattern and frequency of prodromal symptoms/behaviors associated with onset of BPI disorder during childhood or adolescence.

METHODS

Parental informants were interviewed annually using structured and semi-structured interviews to record medical, developmental and behavioral/symptomatic data for their children in two samples. The bipolar sample had 115 children with a BPI parent. The control sample had 106 children of well parents, with and without a positive family history for mood disorders. A panel of clinicians assigned risk ratings independently and blind to family relations.

RESULTS

Eight children, age 13 or older, onset with BPI in the bipolar sample compared with one in the control sub-sample (well parent of a BPI sibling). The specific "pre-school" behaviors/symptoms that most identified children with BPI from well children in control samples were: sensitivity, crying, hyper-alertness, anxiety/worry and somatic complaints. During school years, parents reported mood (sad) and energy changes (low not high) decreased sleep and fearfulness as key symptoms.

LIMITATIONS

The sample of 9 BPI onsets is small. However, a variable age of onset means many children remain at risk. Although not statistically significant, 34.6% of the bipolar sample youngsters carry risk ratings compared to 15.2% among controls.

CONCLUSIONS

The miniclusters of prodromal features that emerged pre-school (ages 1-6), were "episodic" through childhood (7-12) and appeared to mimic adult recurrent illness. Prepubertal onset with mania did not occur. The pattern of prodromal symptoms has clinical relevance for its potential predictive value for onset with BPI disorder and early intervention.

Depression and anxiety diagnoses are not associated with delayed resolution of abnormal mammograms and pap tests among vulnerable women

BACKGROUND

Delays in care after abnormal cancer screening contribute to disparities in cancer outcomes. Women with psychiatric disorders are less likely to receive cancer screening and may also have delays in diagnostic resolution after an abnormal screening test.

OBJECTIVE

To determine if depression and anxiety are associated with delays in resolution after abnormal mammograms and Pap tests in a vulnerable population of urban women.

DESIGN

We conducted retrospective chart reviews of electronic medical records to identify women who had a diagnosis of depression or anxiety in the year prior to the abnormal mammogram or Pap test. We used time-to-event analysis to analyze the outcome of time to resolution after abnormal cancer screening, and Cox proportional hazards regression modeling to control for confounding.

PARTICIPANTS

Women receiving care in six Boston-area community health centers 2004-2005: 523 with abnormal mammograms, 474 with abnormal Pap tests.

RESULTS

Of the women with abnormal mammogram and pap tests, 19% and 16%, respectively, had co-morbid depression. There was no difference in time to diagnostic resolution between depressed and not-depressed women for those with abnormal mammograms (aHR = 0.9, 95 CI 0.7,1.1) or Pap tests (aHR = 0.9, 95 CI 0.7,1.3).

CONCLUSIONS

An active diagnosis of depression and/or anxiety in the year prior to an abnormal mammogram or Pap test was not associated with a prolonged time to diagnostic resolution. Our findings imply that documented mood disorders do not identify an additional barrier to resolution after abnormal cancer screening in a vulnerable population of women.

Effect of ethacrynic acid on the sodium- and potassium-activated adenosine triphosphatase activity and expression in Old Order Amish bipolar individuals

BACKGROUND

There are numerous reports of abnormalities in the expression of the sodium- and potassium-activated adenosine triphosphatase (Na,K-ATPase) in response to an ionic stress with ethacrynic acid (ECA) challenge in bipolar subjects. However, all of these studies have been in out-bred populations. In an attempt to reduce the genetic variability associated with this observation, we examined this phenomenon within an isolated breeding population.

METHODS

We studied 36 lymphoblastoid cell lines obtained from Old Order Amish individuals who had bipolar disorder, type I (16), or were unaffected siblings of the same gender (9) or unrelated normal controls(11). Cells were treated with 10(-)(5)M ECA for 3 days after which Na,K-ATPase alpha1 protein expression and activity ([(3)H]-ouabain binding, (86)Rb-uptake, and intracellular sodium and potassium concentrations) were measured.

RESULTS

Cells from bipolar patients expressed less Na,K-ATPase as measured by immunoblot analysis after ECA treatment (0.94 + or - SD 0.13 relative units) compared to unaffected siblings (1.06 + or - 0.12, P = 0.029) and Old Order Amish normal controls (1.06 + or - 0.14, P = 0.0004). None of the other variables studied were different.

LIMITATIONS

This is a study of peripheral cells which do not express all of the Na,K-ATPase expressed in the brain. The observed difference is small.

CONCLUSIONS

Ethacrynic-acid-stimulated lymphoblast sodium pump expression in Old Order Amish bipolar subjects is reduced compared to Amish controls.

The modified SCID Hypomania Module (SCID-Hba): a detailed systematic phenomenologic probing

Diagnosing past hypomania is a difficult task. Current structured interviews (e.g. CIDI, SCID) limit the ability to probe for hypomania. A modified SCID Hypomania Module was published by us (Benazzi and Akiskal, J Affect Disord 2003; Akiskal and Benazzi, J Clin Psychiatry 2005) in order to overcome the limitations of structured interviewing. Our papers outlined the framework of the modified SCID. In response to requests from many readers of this journal and other clinicians and investigators, we are hereby providing a more explicit step-by-step phenomenologic probing interview. DSM-IV criteria have to be met, but the probing for hypomania is very different from that of the SCID. All past hypomanic symptoms are assessed. No negative meaning is given to symptoms, as hypomania often improves functioning and it is seen by patients as a state of well being. The first step is probing for overactivity (increase in goal-directed activity), because observable behaviors are easier to remember by patients and key informants. There is no gold-standard for overactivity: each person becomes his/her own standard to 'measure' a clear-cut departure form the usual behavior. Questions, correspondingly, can change from patient to patient. The emotions associated with behavioral change are easier to be remembered than asking them first, as in the structured interviews. Structured interviews have mood change (elation, irritability) as stem question (corresponding to the criterion A of DSM-IV, which postulates that it must always be present). However, apart from a likely recall bias of past emotions, the description of mood change appears more or less negative in structured interviews (to increase specificity but by much reducing sensitivity, i.e. the false-negatives). Presenting mood change as simply having been more elated/irritable than usual can easily be interpreted as normal mood fluctuations, while presenting mood change as much more than usual could be understood as a severe mental disorder. Both ways are likely to lead to a negative response, moving the interviewers to unipolar disorders (the skip-out instruction). Our modified SCID is a fully semi-structured interview: many questions are asked about each symptom to make the question understandable according to each patient, and, very importantly, examples of the 'events' are systematically asked to check understanding and clinical relevance. Our interview follows DSM-IV criteria (apart from the minimum duration, 2 days versus DSM-IV 4 days), i.e. mood change must always been present, but our probing detects more hypomanic episodes than the SCID.

Genomic landscape of a three-generation pedigree segregating affective disorder

Bipolar disorder (BPD) is a common psychiatric illness with a complex mode of inheritance. Besides traditional linkage and association studies, which require large sample sizes, analysis of common and rare chromosomal copy number variants (CNVs) in extended families may provide novel insights into the genetic susceptibility of complex disorders. Using the Illumina HumanHap550 BeadChip with over 550,000 SNP markers, we genotyped 46 individuals in a three-generation Old Order Amish pedigree with 19 affected (16 BPD and three major depression) and 27 unaffected subjects. Using the PennCNV algorithm, we identified 50 CNV regions that ranged in size from 12 to 885 kb and encompassed at least 10 single nucleotide polymorphisms (SNPs). Of 19 well characterized CNV regions that were available for combined genotype-expression analysis 11 (58%) were associated with expression changes of genes within, partially within or near these CNV regions in fibroblasts or lymphoblastoid cell lines at a nominal P value <0.05. To further investigate the mode of inheritance of CNVs in the large pedigree, we analyzed a set of four CNVs, located at 6q27, 9q21.11, 12p13.31 and 15q11, all of which were enriched in subjects with affective disorders. We additionally show that these variants affect the expression of neuronal genes within or near the rearrangement. Our analysis suggests that family based studies of the combined effect of common and rare CNVs at many loci may represent a useful approach in the genetic analysis of disease susceptibility of mental disorders.

Parental concordance and offspring risk for anxiety, conduct, depressive, and substance use disorders

BACKGROUND

Although parental concordance for any psychiatric disorder is known to be associated with elevated risk for offspring disorder, little evidence is currently available from prospective longitudinal studies regarding the association of parental concordance with offspring risk for anxiety, conduct, depressive, and substance use disorders.

SAMPLING AND METHODS

Psychiatric interviews were conducted with 593 mothers and their biological offspring at mean offspring ages 14, 16, 22, and 33.

RESULTS

Offspring risk for >or=1 psychiatric disorder was significantly greater if both parents had a lifetime history of psychiatric disorder than if only one parent had a lifetime history of disorder. Parental concordance for generalized anxiety disorder (GAD) was associated with a significant increase in offspring risk for anxiety disorders, above and beyond the risk attributable to having one affected parent. In addition, parental concordance for GAD was associated with elevated risk for offspring depressive disorders, and parental concordance for substance use disorders was associated with elevated offspring risk for conduct disorder.

CONCLUSIONS

Parental concordance for GAD may be associated with elevated risk for offspring anxiety disorder, above and beyond the risk associated with having one affected parent.

Prospective study of prodromal features for bipolarity in well Amish children

OBJECTIVE

A prospective study of psychiatrically well Amish children to determine differences in the frequency and pattern of clinical features that may be prodromal for bipolar I disorder.

METHOD

Children with a bipolar I parent (n = 100) and children of well parents in a matched control sample (n = 110) were assessed annually for 7 years with semistructured interviews covering medical/developmental features and symptoms/behaviors that are possibly prodromal for bipolarity. Randomized histories of these 210 children were evaluated blindly by 4 clinicians for independent ratings of risk for bipolarity.

RESULTS

Thirty-eight percent of the children of bipolar parents were rated as at risk compared with 17% of children in the control sample. Most control sample children with risk ratings had well parents with a bipolar sibling (i.e., family history positive). Children with family histories negative for mental illness rarely received even a low risk rating. Clinical features significantly (p <or=.05) more frequent among children of a bipolar parent included mood lability, low energy, anxious/worried, hyper-alert, attention problems/distractible and school role impairment, easily excited, sensitivity, somatic complaints, and stubborn/determined.

CONCLUSION

Mini-clusters of early possible predictors suggest a natural history of episodic prodromal features rather than the chronic symptom pattern sometimes described for children at risk for bipolar disorder.

Prodromal symptoms before onset of manic-depressive disorder suggested by first hospital admission histories

OBJECTIVE

A priority for research on manic-depressive or bipolar I disorder (BPI) for children and adolescents has been to search for early predictors of the illness.

METHOD

Medical record data were reviewed and systematically coded for a sample of 58 adult patients (32 males/26 females) with confirmed diagnoses of BPI to identify prodromal features and possible patterns of symptoms from the Amish Study.

RESULTS

The most frequently reported symptoms included episodic changes in mood (depressed and irritable) and energy plus anger dyscontrol, with no significant gender differences. A progression of ages is seen for the most commonly reported symptoms prior to age 16. The time interval was 9 to 12 years between appearance of the first symptoms and onset of a documented BPI syndrome.

CONCLUSIONS

The data suggest testable hypotheses about specific symptoms and behaviors that may be useful for the early detection of children at highest risk for developing manic-depressive disorder.

A genome-wide search for chromosomal loci linked to mental health wellness in relatives at high risk for bipolar affective disorder among the Old Order Amish

Bipolar affective disorder (BPAD; manic-depressive illness) is characterized by episodes of mania and/or hypomania interspersed with periods of depression. Compelling evidence supports a significant genetic component in the susceptibility to develop BPAD. To date, however, linkage studies have attempted only to identify chromosomal loci that cause or increase the risk of developing BPAD. To determine whether there could be protective alleles that prevent or reduce the risk of developing BPAD, similar to what is observed in other genetic disorders, we used mental health wellness (absence of any psychiatric disorder) as the phenotype in our genome-wide linkage scan of several large multigeneration Old Order Amish pedigrees exhibiting an extremely high incidence of BPAD. We have found strong evidence for a locus on chromosome 4p at D4S2949 (maximum GENEHUNTER-PLUS nonparametric linkage score = 4.05, P = 5. 22 x 10(-4); SIBPAL Pempirical value <3 x 10(-5)) and suggestive evidence for a locus on chromosome 4q at D4S397 (maximum GENEHUNTER-PLUS nonparametric linkage score = 3.29, P = 2.57 x 10(-3); SIBPAL Pempirical value <1 x 10(-3)) that are linked to mental health wellness. These findings are consistent with the hypothesis that certain alleles could prevent or modify the clinical manifestations of BPAD and perhaps other related affective disorders.

Writing Amish culture into genes: biological reductionism in a study of manic depression

Critical realism is used to explore the problem of reductionism in a classic (the Amish Study) and widely-cited study of manic depression. Along with related ideas drawn from the works of R.C. Lewontin, Arthur Kleinman, and Byron Good, it is shown that natural and social scientists deploy atomistic and holistic reductionism; this, in turn, leads to the construction of artificially 'closed systems' through the control of variables or exogenous forces. The psychiatric genetic studies of the Amish were predicated on the assumption that Amish society is homogeneous and unchanging and, therefore, closed. We conclude by arguing that interactions between behaviors and genes, where they exist, take place only within open systems, characterized by multiple mechanisms-social and biological-that together co-determine any event. To move forward, it is argued, behavior and gene research requires recognition and resolution of the philosophical conundrums that accompany reductionism.

Linkage studies suggest a possible locus for bipolar disorder near the velo-cardio-facial syndrome region on chromosome 22

Velo-cardio-facial syndrome (VCFS) is a congenital anomaly characterized by multiple dysmorphisms, cleft palate, cardiac anomalies, and learning disabilities, that results from a microdeletion of chromosome 22q11. An increased prevalence of psychiatric illness has been observed, with both schizophrenia and bipolar disorder commonly being diagnosed. For these reasons, the VCFS region is an interesting candidate region for bipolar disorder. We examined this region in 17 bipolar families from three populations: 13 families from the general North American population (University of California, San Diego/University of British Columbia, UCSD/UBC), three larger families from New York, and a portion of Old Order Amish pedigree 110. Three microsatellite markers spanning 13 cM around the VCFS region were genotyped in all the families. A maximum lod score of 2.51 was obtained in the UCSD/UBC families under a dominant model at D22S303. In the combined family set, maximum lod scores of 1.68 and 1.28 were obtained at this marker under dominant and recessive models, respectively. Four additional markers were subsequently typed in selected positive families, and yielded positive lods at 6 of 7 markers spanning 18 cM in this region. Nonparametric, multipoint analyses using the affected pedigree member (APM) method also yielded suggestive evidence for linkage in both the UCSD/UBC family set (P = 0.0024) and in the combined families (P = 0.017). Affected sibpair analyses were similarly positive in the UCSD/UBC families (P = 0.017), and in the combined families (P = 0.004). These results are suggestive of a possible locus for bipolar disorder near the VCFS region on chromosome 22.

A genome-wide search for chromosomal loci linked to bipolar affective disorder in the Old Order Amish

The most characteristic features of bipolar affective disorder (manic-depressive illness) are episodes of mania (bipolar I, BPI) or hypomania (bipolar II, BPII) interspersed with periods of depression. Manic-depressive illness afflicts about one percent of the population, and if untreated, is associated with an approximately 20% risk of suicide. Twin, family and adoption studies provide compelling evidence for a partial genetic aetiology, but the mode(s) of inheritance has not been identified. Nonetheless, the majority of genetic linkage studies have assumed classical mendelian inheritance attributable to a single major gene. Although segregation analyses have yielded inconsistent results (with most studies rejecting a single locus inheritance model), the best single gene model is dominant inheritance if only BPI is considered. Reported linkages of bipolar affective disorder on chromosomes 11, 18, 21 and X have been difficult to substantiate, and additional studies are required for replication or exclusion of these regions. We now present the results of our genome-wide linkage analyses that provide evidence that regions on chromosomes 6, 13 and 15 harbour susceptibility loci for bipolar affective disorder, suggesting that bipolar affective disorder in the Old Order Amish is inherited as a complex trait.

Complex segregation analyses of old order Amish families ascertained through bipolar I individuals

Specific genetic hypotheses about the mode of transmission of bipolar affective disorders were examined by performing complex segregation analyses of Old Order Amish families. The analyses were performed on 1) the total set of 42 families including 689 relatives, 2) a subset of 19 families consisting of those kindreds sharing common ancestors within three generations that contained 333 relatives, and 3) a subset of 23 more distantly related families with 356 relatives. When all 42 families were included in the analyses, the specific mode of transmission that could be distinguished was dependent upon the diagnostic scheme used in the analysis. An autosomal dominant mode of inheritance could be rejected when relatives with bipolar I, atypical bipolar, major depressive disorder, and hypomania were included as affected. When analyses included only the subset of families more closely related, an autosomal dominant inheritance model was found to be consistent with transmission of BP I disorder. It was not possible to distinguish between other transmission models with broader diagnostic schemes in this subset of families. Finally, results of analyses on the subset of more distantly related families suggest that there is a significant proportion of Old Order Amish families in which the genetic factors contributing to the expression of bipolar illness are either polygenic or oligogenic.

Initial report of a genome search for the affective disorder predisposition gene in the old order Amish pedigrees: chromosomes 1 and 11

Family data have suggested that some forms of major affective disorder are genetic. Certain of the Old Order Amish pedigrees have a familial form of the disease. In this report we present the results of genetic analyses under autosomal dominant mode of transmission with reduced penetrance and three different disease hierarchies. The pedigrees were genotyped with 28 markers from chromosome 1 and 23 markers from chromosomes 11. None of the markers result in a significantly positive lod score.

A linkage study of distal chromosome 5q and bipolar disorder

There are well-established abnormalities of hypothalamic-pituitary-adrenal (HPA) axis and beta 2 adrenergic receptor function in affective disorders. The genes for the glucocorticoid receptor (GRL) and the beta 2 adrenergic receptor (ADRB2) have been cloned and mapped to distal chromosome 5q. In this study, we have examined polymorphisms of these two candidate genes and other nearby markers for linkage to bipolar disorder in Amish pedigree 110 and three large Icelandic pedigrees. These loci were tested for linkage in two-point and multipoint analyses using a model of autosomal dominant transmission with age-dependent reduced penetrance. Two-point analyses revealed a maximum LOD score of 1.14 at theta = 0.20 from GRL. Linkage could be excluded to ADRB2, as well as to three nearby anonymous markers, D5S207, D5S70, and D5S119. Analyses of another anonymous marker, D5S36, were inconclusive. Multipoint analyses excluded linkage to a 55 cM region including the interval between D5S207 and D5S36 and flanking regions, with the exception of a 7 cM interval between GRL and ADRB2. Despite the intriguing positive LOD score obtained with GRL, linkage to bipolar disorder could not be demonstrated in the region examined.

Cation transport mediated by Na+,K(+)-adenosine triphosphatase in lymphoblastoma cells from patients with bipolar I disorder, their relatives, and unrelated control subjects

In an investigation of cation transport in bipolar affective disorder, we have measured parameters related to Na+,K(+)-adenosine triphosphatase, the enzyme that carries out active transport of sodium and potassium, in lymphoblastoid cells cultured from patients with bipolar affective disorder, age-matched nonaffected family relatives, and unrelated control subjects. Patients had lower ion transport per cell and per transport enzyme site than did related or unrelated control subjects. The rate of transport per cell appeared higher in nonaffected relatives of patients than in unrelated control subjects, though this difference did not reach significance. These data suggest that abnormally regulated ion transport may be associated with bipolar affective disorder independently of clinical state.

Linkage of bipolar affective disorders to markers on chromosome 11p is excluded in a second lateral extension of Amish pedigree 110

Linkage between markers on chromosome 11p and bipolar affective disorders can be excluded in a second large lateral extension of the original Amish Pedigree 110. These results, together with previous negative linkage findings, suggest that there is not one single gene on 11p conferring susceptibility for bipolar affective disorders among the Old Order Amish.

Re-evaluation of the linkage relationship between chromosome 11p loci and the gene for bipolar affective disorder in the Old Order Amish

Reanalysis of an Old Order Amish pedigree, to include several new individuals and two changes in clinical status, markedly reduces the probability of linkage between bipolar affective disorder and the Harvey-ras-1 oncogene and insulin loci on chromosome 11. This linkage can be excluded using a large lateral extension of the original Amish pedigree.

Description of Amish Study data set

A brief description is given on the ascertainment methods and diagnostic procedures for bipolar affective disorder patients and their relatives in Amish pedigrees. Data on a sample of five bipolar families are provided, including conventional blood typings, serum protein and RFLP data.

Reliability and relationship of various ages of onset criteria for major affective disorder

This paper presents data on six different clinical definitions (indices) of age of onset for major affective disorders. The inter-rater reliability for each index and the relationships among these indices are discussed. Age of onset for impairment with affective symptoms was found to be a reliable and useful index of early onset. It discriminated between unipolar depressed subjects and both bipolar I and bipolar II subjects.

Bipolar affective disorders linked to DNA markers on chromosome 11

An analysis of the segregation of restriction fragment length polymorphisms in an Old Order Amish pedigree has made it possible to localize a dominant gene conferring a strong predisposition to manic depressive disease to the tip of the short arm of chromosome 11.

Search for a gene that predisposes individuals to BPI disorder

To determine the role of genetics in bipolar affective disorders it was necessary to have correct diagnoses and large homogenous population(s). To identify a marker linked to the disease two additional factors were important, a correct model for genetic transmission and highly polymorphic DNA markers. With the establishment of a linked marker the aim is to identify the susceptibility gene. Two approaches are the prediction of candidate genes and/or the determination of a physical map of the region.