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Delineation of structural variants (SVs) at sequence resolution in highly repetitive genomic regions has long been intractable. The sequence properties, origins, and functional effects of classes of genomic rearrangements such as ring chromosomes and Robertsonian translocations thus remain unknown. To resolve these complex structures, we leveraged several recent milestones in the field, including (1) the emergence of long-read sequencing, (2) the gapless telomere-to-telomere (T2T) assembly, and (3) a tool (BigClipper) to discover chromosomal rearrangements from long reads. We applied these technologies across 13 cases with ring chromosomes, Robertsonian translocations, and complex SVs that were unresolved by short reads, followed by validation using optical genome mapping (OGM). Our analyses resolved 10 of 13 cases, including a Robertsonian translocation and all ring chromosomes. Multiple breakpoints were localized to genomic regions previously recalcitrant to sequencing such as acrocentric p-arms, ribosomal DNA arrays, and telomeric repeats, and involved complex structures such as a deletion-inversion and interchromosomal dispersed duplications. We further performed methylation profiling from long-read data to discover phased differential methylation in a gene promoter proximal to a ring fusion, suggesting a long-range position effect (LRPE) with heterochromatin spreading. Breakpoint sequences suggested mechanisms of SV formation such as microhomology-mediated and non-homologous end-joining, as well as non-allelic homologous recombination. These methods provide some of the first glimpses into the sequence resolution of Robertsonian translocations and illuminate the structural diversity of ring chromosomes and complex chromosomal rearrangements with implications for genome biology, prediction of LRPEs from integrated multi-omics technologies, and molecular diagnostics in rare disease cases., Competing Interests: Declaration of interests The Talkowski laboratory receives reagents and/or research support from Illumina Inc and Microsoft Inc. Bionano Genomics provided data and analysis support for Optical Genome Mapping. J.H. and A.R.H. are employees of Bionano Genomics, Inc., (Copyright © 2024 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.)

Background: Eating disorders have one of the highest mortality rates among psychiatric illnesses. Timely intervention is crucial for effective treatment, as eating disorders tend to be chronic and difficult to manage if left untreated. Clinical practice guidelines play a vital role in improving healthcare delivery, aiming to minimize variations in care and bridge the gap between research and practice. However, research indicates an active guideline implementation approach is crucial to effective uptake., Methods: Mixed methods will be used to inform and evaluate our guideline implementation approach. Semi-structured focus groups will be conducted in each of the eight provinces in Canada. Each focus group will comprise 8-10 key stakeholders, including clinicians, program administrators, and individuals with lived experience or caregivers. Qualitative data will be analyzed using conventional content analysis and the constant comparison technique and the results will be used to inform our implementation strategy. The study will then evaluate the effectiveness of our implementation approach through pre- and post-surveys, comparing changes in awareness, use, and impact of the guidelines in various stakeholder groups., Discussion: Through a multifaceted implementation strategy, involving the co-creation of educational materials, tailored training, and context-specific strategies, this study intends to enhance guideline uptake and promote adherence to evidence-based practices. Our study will also contribute valuable information on the impact of our implementation strategies., (© 2023. The Author(s).)

Objective: This study investigated treatment-engagement fears, self-efficacy, and accommodating and enabling in mothers and fathers of adolescent and adult children with eating disorders., Methods: This study involved a secondary analysis of pre-treatment data from a subsample of 143 parents (95 mothers; 48 fathers) from a Canada-wide multi-site study. Parents completed the Caregiver Traps Scale, Parents Versus Anorexia Scale, and the Accommodation and Enabling Scale for Eating Disorders. Data were analysed using factorial Multivariate Analysis of Variance and mediation via multiple regression., Results: Mothers reported higher levels of treatment-engagement fears than fathers. Among mothers, higher fear predicted lower self-efficacy and more accommodating and enabling behaviours. Among fathers, neither fear nor self-efficacy predicted accommodating and enabling. No differences in treatment-engagement fear or self-efficacy between parents of adolescent child and adult children were found at pre-treatment., Conclusions: Mothers' and fathers' experience different levels of fear related to their involvement in their ill-child's treatment at pre-treatment, and that fear is uniquely related to variables that impact treatment outcomes. There is a need to support parents even when their child is an adult. This study can inform family-based treatments vis-a-vis tailoring interventions for mothers and fathers and providing support to parents of children with eating disorders across the lifespan., (© 2022 Eating Disorders Association and John Wiley & Sons Ltd.)

Objective: The COVID-19 pandemic has had detrimental effects on mental health. Literature on the impact on individuals with eating disorders is slowly emerging. While outpatient eating disorder services in Canada have attempted to transition to virtual care, guidelines related to optimal virtual care in this field are lacking. As such, the objective of our Canadian Consensus Panel was to develop clinical practice guidelines related to the provision of virtual care for children, adolescents, and emerging adults living with an eating disorder, as well as their caregivers, during the COVID-19 pandemic and beyond., Methods: Using scoping review methodology (with literature in databases from 2000 to 2020 and grey literature from 2010 to 2020), the Grading of Recommendations, Assessment, Development, and Evaluation system, the Appraisal of Guidelines, Research and Evaluation tool, and a panel of diverse stakeholders from across Canada, we developed high quality treatment guidelines that are focused on virtual interventions for children, adolescents, and emerging adults with eating disorders, and their caregivers., Results: Strong recommendations were supported specifically in favour of in-person medical evaluation when necessary for children, adolescents, and emerging adults, and that equity-seeking groups and marginalized youth should be provided equal access to treatment. For children and adolescents, weak recommendations were supported for telehealth family-based treatment (FBT) and online guided parental self-help FBT. For emerging adults, internet cognitive-behavioural therapy (CBT)-based guided self-help was strongly recommended. Weak recommendations for emerging adults included CBT-based group internet interventions as treatment adjuncts, internet-based relapse prevention Maudsley Model of Anorexia Nervosa Treatment for Adults (MANTRA) guided self-help, telehealth relapse prevention using MANTRA, and guided CBT-based smartphone apps as treatment adjuncts. For caregivers of children and adolescents, weak recommendations were supported for virtual parent meal support training, and moderated online caregiver forums and support groups. For caregivers of emerging adults, guided parental self-help CBT was strongly recommended, and unguided caregiver psychoeducation self-help was weakly recommended., Conclusions: Several gaps for future work were identified including the impact of sex, gender, race, and socioeconomic status on virtual care among children, adolescents, and emerging adults with eating disorders, as well as research on more intensive services, such as virtual day hospitals.

Context: Kallmann syndrome (KS) is a rare, genetically heterogeneous Mendelian disorder. Structural defects in KS patients have helped define the genetic architecture of gonadotropin-releasing hormone (GnRH) neuronal development in this condition., Objective: Examine the functional role a novel structural defect affecting a long noncoding RNA (lncRNA), RMST, found in a KS patient., Design: Whole genome sequencing, induced pluripotent stem cells and derived neural crest cells (NCC) from the KS patient were contrasted with controls., Setting: The Harvard Reproductive Sciences Center, Massachusetts General Hospital Center for Genomic Medicine, and Singapore Genome Institute., Patient: A KS patient with a unique translocation, t(7;12)(q22;q24)., Interventions/main Outcome Measure/results: A novel translocation was detected affecting the lncRNA, RMST, on chromosome 12 in the absence of any other KS mutations. Compared with controls, the patient's induced pluripotent stem cells and NCC provided functional information regarding RMST. Whereas RMST expression increased during NCC differentiation in controls, it was substantially reduced in the KS patient's NCC coincident with abrogated NCC morphological development and abnormal expression of several "downstream" genes essential for GnRH ontogeny (SOX2, PAX3, CHD7, TUBB3, and MKRN3). Additionally, an intronic single nucleotide polymorphism in RMST was significantly implicated in a genome-wide association study associated with age of menarche., Conclusions: A novel deletion in RMST implicates the loss of function of a lncRNA as a unique cause of KS and suggests it plays a critical role in the ontogeny of GnRH neurons and puberty., (© Endocrine Society 2019. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Objectives: Eating disorders are common and serious conditions affecting up to 4% of the population. The mortality rate is high. Despite the seriousness and prevalence of eating disorders in children and adolescents, no Canadian practice guidelines exist to facilitate treatment decisions. This leaves clinicians without any guidance as to which treatment they should use. Our objective was to produce such a guideline., Methods: Using systematic review, the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system, and the assembly of a panel of diverse stakeholders from across the country, we developed high quality treatment guidelines that are focused on interventions for children and adolescents with eating disorders., Results: Strong recommendations were supported specifically in favour of Family-Based Treatment, and more generally in terms of least intensive treatment environment. Weak recommendations in favour of Multi-Family Therapy, Cognitive Behavioural Therapy, Adolescent Focused Psychotherapy, adjunctive Yoga and atypical antipsychotics were confirmed., Conclusions: Several gaps for future work were identified including enhanced research efforts on new primary and adjunctive treatments in order to address severe eating disorders and complex co-morbidities., Competing Interests: Competing interestsThe authors declare that they have no competing interests., (© The Author(s). 2020.)

Importance: Identifying measures that are associated with the cytosine-adenine-guanine (CAG) expansion in individuals before diagnosis of Huntington disease (HD) has implications for designing clinical trials., Objective: To identify the earliest features associated with the motor diagnosis of HD in the Prospective Huntington at Risk Observational Study (PHAROS)., Design, Setting, and Participants: A prospective, multicenter, longitudinal cohort study was conducted at 43 US and Canadian Huntington Study Group research sites from July 9, 1999, through December 17, 2009. Participants included 983 unaffected adults at risk for HD who had chosen to remain unaware of their mutation status. Baseline comparability between CAG expansion (≥37 repeats) and nonexpansion (<37 repeats) groups was assessed. All participants and investigators were blinded to individual CAG analysis. A repeated-measures analysis adjusting for age and sex was used to assess the divergence of the linear trend between the expanded and nonexpanded groups. Data were analyzed from April 27, 2010, to September 3, 2013., Exposure: Huntington disease mutation status in individuals with CAG expansion vs without CAG expansion., Main Outcomes and Measures: Unified Huntington's Disease Rating Scale motor (score range, 0-124; higher scores indicate greater impairment), cognitive (symbol digits modality is the total number of correct responses in 90 seconds; lower scores indicate greater impairment), behavioral (score range, 0-176; higher scores indicate greater behavioral symptoms), and functional (Total Functional Capacity score range, 0-13; lower scores indicate reduced functional ability) domains were assessed at baseline and every 9 months up to a maximum of 10 years., Results: Among the 983 research participants at risk for HD in the longitudinal cohort, 345 (35.1%) carried the CAG expansion and 638 (64.9%) did not. The mean (SD) duration of follow-up was 5.8 (3.0) years. At baseline, participants with expansions had more impaired motor (3.0 [4.2] vs 1.9 [2.8]; P < .001), cognitive (P < .05 for all measures except Verbal Fluency, P = .52), and behavioral domain scores (9.4 [11.4] vs 6.5 [8.5]; P < .001) but not significantly different measures of functional capacity (12.9 [0.3] vs 13.0 [0.2]; P = .23). With findings reported as mean slope (95% CI), in the longitudinal analyses, participants with CAG expansions showed significant worsening in motor (0.84 [0.73 to 0.95] vs 0.03 [-0.05 to 0.11]), cognitive (-0.54 [-0.67 to -0.40] vs 0.22 [0.12 to 0.32]), and functional (-0.08 [-0.09 to -0.06] vs -0.01 [-0.02 to 0]) measures compared with those without expansion (P < .001 for all); behavioral domain scores did not diverge significantly between groups., Conclusions and Relevance: Using these prospectively accrued clinical data, relatively large treatment effects would be required to mount a randomized, placebo-controlled clinical trial involving premanifest HD individuals who carry the CAG expansion.

Carers often feel disempowered and engage in behaviours that inadvertently enable their loved one's ED symptoms and yet little is known regarding these processes. This study examined the relationships among fear, self-blame, self-efficacy, and accommodating and enabling behaviours in 137 carers of adolescents and adults with ED. The results revealed that fear and self-blame predicted low carer self-efficacy in supporting their loved one's recovery as well as the extent to which carers reported engaging in recovery-interfering behaviours. The relevance of these findings are discussed in the context of family-oriented ED therapies and highlight the importance for clinicians to attend to and help to process strong emotions in carers, in order to improve their supportive efforts and, ultimately, ED outcomes.

Objective: To explore and describe philosophies and characteristics of intensive eating disorder (ED) treatment programs based in tertiary care institutions across Canada., Method: A ninety-item survey examining ED services for adolescents was developed, piloted, and completed by 11 programs across Canada. Information pertaining to program characteristics and components, governance, staffing, referrals, assessments, therapeutic modalities in place, nutritional practices, and treatment protocols were collected., Results: The results highlight the diversity of programming available but also the lack of a unified approach to intensive eating disorder treatment in youth., Conclusions: This report provides important baseline data that offers a framework that programs can use to come together to establish assessment and treatment protocols as well as a process for outcome evaluation. Continued collaboration will be essential moving forward to ensure Canadian youth, regardless of geographic location, receive the necessary treatment required to attain and sustain recovery.

The Huntington's disease gene product, huntingtin, is indispensable for neural tube formation, but its role is obscure. We studied neurulation in htt-null embryonic stem cells and htt-morpholino zebrafish embryos and found a previously unknown, evolutionarily recent function for this ancient protein. We found that htt was essential for homotypic interactions between neuroepithelial cells; it permitted neurulation and rosette formation by regulating metalloprotease ADAM10 activity and Ncadherin cleavage. This function was embedded in the N terminus of htt and was phenocopied by treatment of htt knockdown zebrafish with an ADAM10 inhibitor. Notably, in htt-null cells, reversion of the rosetteless phenotype occurred only with expression of evolutionarily recent htt heterologues from deuterostome organisms. Conversely, all of the heterologues that we tested, including htt from Drosophila melanogaster and Dictyostelium discoideum, exhibited anti-apoptotic activity. Thus, anti-apoptosis may have been one of htt’s ancestral function(s), but, in deuterostomes, htt evolved to acquire a unique regulatory activity for controlling neural adhesion via ADAM10-Ncadherin, with implications for brain evolution and development.

Background: Advances in genetic technology have revealed that variation in the same gene can cause both rare familial and common sporadic forms of the same disease. Cerebral amyloid angiopathy (CAA), a common cause of symptomatic intracerebral hemorrhage (ICH) in the elderly, can also occur in families in an autosomal dominant pattern. The majority of affected families harbor mutations in the Beta amyloid Peptide (Aβ) coding region of the gene for amyloid precursor protein (APP) or have duplications of chromosomal segments containing APP., Methodology/principal Findings: A total of 58 subjects with a diagnosis of probable or definite CAA according to validated criteria were included in the present study. We sequenced the Aβ coding region of APP in 58 individuals and performed multiplex ligation-dependent probe amplification to determine APP gene dosage in 60. No patient harbored a known or novel APP mutation or gene duplication. The frequency of mutations investigated in the present study is estimated to range from 0% to 8% in individuals with probable CAA in the general population, based on the ascertained sample size., Conclusions/significance: We found no evidence that variants at loci associated with familial CAA play a role in sporadic CAA. Based on our findings, these rare highly-penetrant mutations are unlikely to be seen in sporadic CAA patients. Therefore, our results do not support systematic genetic screening of CAA patients who lack a strong family history of hemorrhage or dementia.

Objective: Presymptomatic individuals with the Huntingtin (HTT) CAG expansion mutation that causes Huntington's disease may have higher levels of depressive symptoms than healthy comparison populations. However, the prevalence of HTT CAG repeat expansions among individuals diagnosed with major depressive disorder has not been established., Method: This was a case-control genetic association study of HTT CAG allele size in two discovery cohorts of individuals with major depressive disorder and comparison subjects without major depression as well as a replication cohort of individuals with major depression and comparison subjects without major depression., Results: CAG repeat lengths of 36 or greater were observed in six of 3,054 chromosomes from individuals with major depression, compared with none of 4,155 chromosomes from comparison subjects. In a third cohort, one expanded allele was observed among 1,202 chromosomes in the major depression group, compared with none of 2,678 chromosomes in comparison subjects. No clear pattern of clinical features was shared among individuals with the expanded repeats., Conclusions: In clinical populations of individuals diagnosed with major depression, approximately 3 in 1,000 carried expanded HTT CAG alleles.

The effectiveness of a web-based prevention program designed for elementary school teachers was examined in 78 elementary school teachers and 89 local public health practitioners (who provide support to schools). Participants were assigned to either the intervention (n = 95) or comparison (n = 72) study groups. All participants completed self-report online measures prior to, and following, the 60-day study period assessing knowledge about various factors that influence body image in children and efficacy to fight weight bias in the school. Information was also solicited on the feasibility of, and on the perceived benefit of the web-based program as a knowledge translation tool, in terms of layout and content. The Student Body program was found to be successful in improving knowledge concerning facts about dieting among the teacher participants, and in increasing efficacy to fight weight bias among the public health participants. Overall, the feedback was very positive concerning the layout and content of the Student Body. Participants reported an overall improvement in their awareness about how weight bias can be present in their teaching practices, and how this can trigger body image concerns among their students. Findings have implications for using the web to engage teachers in the prevention of disordered eating among school age children.

Neurofibromatosis 1 (NF1) is a multisystem genetic disorder that primarily affects the skin (freckling and café-au-lait macules), nervous system (neurofibromas, optic gliomas, and learning disabilities), and skeletal system (pseudoarthroses). The interest in pharmacological intervention for patients with NF1 has grown in recent years. However, little is known about the attitudes and priorities of patients, families, and physicians regarding participation in clinical trials. We surveyed 74 adult patients or parents of patients with NF1 and 69 care providers participating in a neurofibromatosis clinic to assess their willingness to participate in clinical trials and their opinions about which conditions they thought were most important to treat. Both patients and care providers are willing to participate in clinical trials for NF1 and both groups rate malignant peripheral nerve sheath tumors as the most urgent for new treatments. There are concordant views among patients and physicians concerning clinical trials for NF1, and patients do not dismiss participation in placebo-controlled trials. Neuroscience nurses are poised to facilitate the research process from conception through implementation as they take the viewpoints of our study populations into consideration.

Context: Previous functional neuroimaging studies have identified a network of brain regions that process aversive stimuli, including anger. A polymorphism near the cyclic adenosine monophosphate response element binding protein gene (CREB1) has recently been associated with greater self-reported effort at anger control as well as risk for antidepressant treatment-emergent suicidality in men with major depressive disorder, but its functional effects have not been studied., Objective: To determine whether this genetic variant is associated with altered brain processing of and behavioral avoidance responses to angry facial expressions., Design and Participants: A total of 28 white participants (mean age, 29.2 years; 13 women) were screened using the Structured Clinical Interview for DSM-IV to exclude any lifetime Axis I psychiatric disorder and were genotyped for rs4675690, a single-nucleotide polymorphism near CREB1., Main Outcome Measures: Blood oxygenation level-dependent signal by functional magnetic resonance imaging in the amygdala, insula, anterior cingulate, and orbitofrontal cortex during passive viewing of photographs of faces with emotional expressions. To measure approach and avoidance responses to anger, an off-line key-press task that traded effort for viewing time assessed valuation of angry faces compared with other expressions., Results: The CREB1-linked single-nucleotide polymorphism was associated with significant differential activation in an extended neural network responding to angry and other facial expressions. The CREB1-associated insular activation was coincident with activation associated with behavioral avoidance of angry faces., Conclusions: A polymorphism near CREB1 is associated with responsiveness to angry faces in a brain network implicated in processing aversion. Coincident activation in the left insula is further associated with behavioral avoidance of these stimuli.

The present study examined the risk of disordered eating and its relation to attempts to lose weight by surveying a Maritime Canadian sample of 247 girls and boys in grades 6, 7 and 8. Current attempts to lose weight were highest in grade 8 girls (41% of girls and 9% of boys) compared with grade 6 (14% of girls and 24% of boys) and grade 7 (21% of girls and 13% of boys) children. Of those trying to lose weight, 71.4% were in the average range for weight and height, 12.2% were overweight and 16.3% were obese. The Children's version of the Eating Attitudes Test (ChEAT) was used to assess eating attitudes and behaviours, and the Rosenberg Self-Esteem Scale was used as a measure of self-esteem. The results showed that 8.5% of the children fell in the high-risk group for disordered eating (ChEAT score 20 or higher). Those in the high-risk group were significantly more likely to fear being overweight (90%), to have tried to lose weight in the past (81%), to be currently trying to lose weight (76%), and to have engaged in binge eating (38%) and self-induced vomiting (24%). The best predictor of membership in the high-risk group for girls was current attempts at weight loss and having lower self-esteem. Only two boys fell in the high-risk group. Body mass index and current weight category (underweight, average, overweight and obese) could not explain the differences between the low- and high-risk groups. Knowing that a child is trying to lose weight can aid in identifying youth at risk for disordered eating, and can provide an opportunity for preventive education.

Objective: To follow the progress of young female adolescents, as risk-taking standardised patients (SPs), and to monitor for adverse affects that role-playing may have on the adolescents., Methods: A prospective design was used in which 11 female adolescents, aged 13-15 years, were recruited from 2 schools. The adolescents were trained to portray risk-taking individuals with a medical condition and were interviewed with their SP mother by final-year medical students 1-3 times a month over 6-14 months. A control group was selected from both schools (n = 6). Main outcome measures were pre- and post-interviews using standardised questionnaires [Achenbach's Youth Self-Report (YSR) and Piers Harris Children's Self Concept Scale (SCS),] and focus groups., Results: The adolescent group simulated 111 interviews (mean per adolescent 10.1, SD = 6.2) each lasting 60-70 minutes. QUANTITATIVE DATA: The pre- and post-scores from the YSR and SCS demonstrated no significant differences within the SP study participants or between the control group vs. the study group. FOCUS GROUP FINDINGS: The initial focus group acted as a debriefing exercise and prompted the adolescents to request that they come out of their role when giving feedback. Subsequent focus group discussion was around the medical student performance and their family doctors., Conclusion: Adolescent females showed no adverse effects when used extensively to portray risk-taking SPs. The focus groups provided the adolescents with an opportunity to debrief together. The adolescent SPs reported benefiting from this study but requested unanimously that they come "out of character" when giving feedback to the medical students.

The molecular basis of tumorigenesis and tumor progression in meningiomas is not fully understood. The neurofibromatosis 2 (NF2) locus is inactivated in 50-60% of sporadic meningiomas, but the genetic basis of sporadic meningiomas not inactivated at the NF2 locus remains unclear. Specifically, there is conflicting data regarding the role of the tumor suppressor gene DAL-1/4.1B. Using microsatellite markers, we studied 63 sporadic meningiomas to determine loss of heterozygosity (LOH) at the NF2 and DAL-1/4.1B loci. Array comparative genomic hybridization analysis of 52 of these tumors was performed to determine copy number changes on chromosomes 18 and 22. Forty-one of 62 informative tumors showed LOH at the NF2 locus (66%) while only 12 of 62 informative tumors (19%) showed LOH of DAL-1/4.1B. Eleven of 12 (92%) tumors with DAL-1/4.1B LOH also had NF2 LOH. Monosomy or large deletions of chromosomes 18 and 22 were the main mechanism for LOH in these tumors. These studies implicate the DAL-1/4.1B locus in sporadic meningiomas less commonly than reported previously, and suggest that it is a progression rather than an initiation locus. Furthermore, we found the majority of meningiomas developed monosomy rather than isodisomy at the NF2 and DAL-1/4.1B loci as the mechanism for LOH.

Huntington's disease (HD) is an autosomal dominant neurodegenerative disease caused by a triplet (CAG) expansion mutation. The length of the triplet repeat is the most important factor in determining age of onset of HD, although substantial variability remains after controlling for repeat length. The Venezuelan HD kindreds encompass 18,149 individuals spanning 10 generations, 15,409 of whom are living. Of the 4,384 immortalized lymphocyte lines collected, 3,989 DNAs were genotyped for their HD alleles, representing a subset of the population at greatest genetic risk. There are 938 heterozygotes, 80 people with variably penetrant alleles, and 18 homozygotes. Analysis of the 83 kindreds that comprise the Venezuelan HD kindreds demonstrates that residual variability in age of onset has both genetic and environmental components. We created a residual age of onset phenotype from a regression analysis of the log of age of onset on repeat length. Familial correlations (correlation +/- SE) were estimated for sibling (0.40 +/- 0.09), parent-offspring (0.10 +/- 0.11), avuncular (0.07 +/- 0.11), and cousin (0.15 +/- 0.10) pairs, suggesting a familial origin for the residual variance in onset. By using a variance-components approach with all available familial relationships, the additive genetic heritability of this residual age of onset trait is 38%. A model, including shared sibling environmental effects, estimated the components of additive genetic (0.37), shared environment (0.22), and nonshared environment (0.41) variances, confirming that approximately 40% of the variance remaining in onset age is attributable to genes other than the HD gene and 60% is environmental.

Thirty-five adolescent girls with eating disorders completed a new brief measure of motivational stage of change and decisional balance. The study supported Prochaska's model of behavioral change demonstrating that decision making was consistently related to stage of readiness to change. The girls generated their individual pros and cons of changing and rated the overall strength of pros and cons. Results showed that the strength of the pros of changing was lowest in Precontemplation and highest in Maintenance. The pros of changing primarily reflected their expectation that "taking action" against the eating disorder would improve their body function and decrease their social anxiety. The cons of changing listed reflected concern that changing would negatively affect their body appearance, and that they were fearful of changing.

Even though we know that anorexia nervosa carries the highest mortality rate of all mental disorders, it is easy to distance ourselves from this fact. Cold hard statistics did not help me to understand what I was likely to experience as a therapist with a dying patient. Putting a face to these statistics, brings the grim reality closer to home for all of us.

This study of a Cognitive Behavior Therapy group examined the process of self-monitoring by adolescent females with eating disorders in group treatment. Five females, aged 17-18 with Anorexia Nervosa (n = 2) and Bulimia Nervosa (n = 3), participated in an 8-week treatment group. Self-monitoring occurred on 50% of the days and was highest during the first 3 weeks of treatment. Commitment to monitoring was related to the girls' self-reported readiness to change. Girls with Anorexia self-monitored as frequently as those with Bulimia. The clinical usefulness of self-monitoring with adolescents is discussed.

In the 1980s, linkage emerged as a route to discovering genetic defects, spurring the rise of genomics and making gene-based approaches available to previously phenotype-orientated researchers. In the post-genomics era, genetics is fundamental to understanding disease at all stages of the pathogenic process.

Neurofibromatosis 2 (NF2) is an autosomal dominant disorder characterized by schwannomas and meningiomas that develop after inactivation of both copies of the NF2 gene. Approximately half of all patients with NF2 have unaffected parents and the disease results from new mutations at the NF2 locus. Loss of heterozygosity (LOH) in tumor specimens due to deletions covering the normal NF2 allele can be used to infer the haplotypes surrounding underlying mutations and determine the allelic origin of new mutations. We studied 71 sporadic NF2 patients using both LOH and pedigree analysis and compared the parental origin of the new mutation with the underlying molecular change. In the 45 informative individuals, 31 mutations (69%) were of paternal and 14 (31%) were of maternal origin (P=0.016). Comparison with corresponding constitutional mutations revealed no correlation between parental origin and the type or location of the mutations. However, in 4 of 6 patients with somatic mosaicism the NF2 mutation was of maternal origin. A slight parent of origin effect on severity of disease was found. Further clinical and molecular studies are needed to determine the basis of these unexpected observations.

Merlin, the neurofibromatosis 2 tumor suppressor protein, has two major isoforms with alternate C termini and is related to the ERM (ezrin, radixin, moesin) proteins. Regulation of the ERMs involves intramolecular and/or intermolecular head-to-tail associations between family members. We have determined whether merlin undergoes similar interactions, and our findings indicate that the C terminus of merlin isoform 1 is able to associate with its N-terminal domain in a head-to-tail fashion. However, the C terminus of isoform 2 lacks this property. Similarly, the N terminus of merlin can also associate with C terminus of moesin. We have also explored the effect of merlin self-association on binding to the regulatory cofactor of Na(+)-H(+) exchanger (NHE-RF), an interacting protein for merlin and the ERMs. Merlin isoform 2 captures more NHE-RF than merlin isoform 1 in affinity binding assays, suggesting that in full-length merlin isoform 1, the NHE-RF binding site is masked because of the self-interactions of merlin. Treatment with a phospholipid known to decrease self-association of ERMs enhances the binding of merlin isoform 1 to NHE-RF. Thus, although isoform 1 resembles the ERM proteins, which transition between inactive (closed) and active (open) states, isoform 2 is distinct, existing only in the active (open) state and presumably constitutively more available for interaction with other protein partners.

The protein huntingtin (htt), aggregated in neuronal nuclear inclusions, is pathognomonic of Huntington's disease (HD). Constructs, translated in vitro from the N terminus of htt, containing either polyQ23 from a normal individual, or polyQ41 or polyQ67 from an HD patient, were all soluble. Transglutaminase (TGase) crosslinked these proteins, and the aggregations did not have the staining properties of amyloid. More TGase-catalyzed aggregates formed when the polyglutamine domain of htt exceeded the pathologic threshold of polyQ36. Furthermore, shorter htt constructs, containing 135 aa or fewer, formed more aggregates than did larger htt constructs. TGase activity in the HD brain was increased compared with the control, with notable increases in cell nuclei. The increased TGase activity was brain specific. In lymphoblastoid cells from HD patients, TGase activity was decreased. TGase-mediated crosslinking of htt may be involved in the formation of the nonamyloidogenic nuclear inclusions found in the HD brain. The staining properties of nuclear inclusions in the HD brain revealed that they were not amyloid.

Forty-two single mothers with young infants were given access to a computer-mediated social support (CMSS) network concerned with parenting issues. The network operated 24 hours per day over a period of 6 months. It permitted public message exchanges, private e-mail, and text-based teleconferencing for as many as 8 participants at any one time. During the 6 month intervention, the 42 women accessed the network over 16,670 times. Individual differences in participation were significantly associated with indices of social isolation from peers. A descriptive analyses of the messages exchanged on the network disclosed that 98% of the replies to concerns posted in the public forum provided positive social support. The majority of the supportive replies fell into the category of emotional support, followed in order by informational and tangible support. Both the self-report data following the intervention, and qualitative data extracted from online discussions indicated that close personal relationships and a sense of community developed in this novel social environment. Finally, an analysis of pretest-posttest changes in the level of parenting stress revealed that mothers who participated regularly in this CMSS community were more likely to report a decrease in parenting stress following the intervention.

We have identified the human homologue of a regulatory cofactor of Na(+)-H+ exchanger (NHE-RF) as a novel interactor for merlin, the neurofibromatosis 2 tumor suppressor protein. NHE-RF mediates protein kinase A regulation of Na(+)-H+ exchanger NHE3 to which it is thought to bind via one of its two PDZ domains. The carboxyl-terminal region of NHE-RF, downstream of the PDZ domains, interacts with the amino-terminal protein 4.1 domain-containing segment of merlin in yeast two-hybrid assays. This interaction also occurs in affinity binding assays with full-length NHE-RF expressed in COS-7 cells. NHE-RF binds to the related ERM proteins, moesin and radixin. We have localized human NHE-RF to actin-rich structures such as membrane ruffles, microvilli, and filopodia in HeLa and COS-7 cells, where it co-localizes with merlin and moesin. These findings suggest that hNHE-RF and its binding partners may participate in a larger complex (one component of which might be a Na(+)-H+ exchanger) that could be crucial for the actin filament assembly activated by the ERM proteins and for the tumor suppressor function of merlin.

Patients with multiple schwannomas without vestibular schwannomas have been postulated to compose a distinct subclass of neurofibromatosis (NF), termed "schwannomatosis." To compare the molecular-genetic basis of schwannomatosis with NF2, we examined the NF2 locus in 20 unrelated schwannomatosis patients and their affected relatives. Tumors from these patients frequently harbored typical truncating mutations of the NF2 gene and loss of heterozygosity of the surrounding region of chromosome 22. Surprisingly, unlike patients with NF2, no heterozygous NF2-gene changes were seen in normal tissues. Examination of multiple tumors from the same patient revealed that some schwannomatosis patients are somatic mosaics for NF2-gene changes. By contrast, other individuals, particularly those with a positive family history, appear to have an inherited predisposition to formation of tumors that carry somatic alterations of the NF2 gene. Further work is needed to define the pathogenetics of this unusual disease mechanism.

Merlin is a tumor suppressor whose inactivation underlies the familial schwannomas and meningiomas of neurofibromatosis 2 and their sporadic counterparts. It bears striking similarity to the ERM proteins, ezrin, radixin and moesin, members of the protein 4.1 superfamily that link proteins in the cytoskeleton and the plasma membrane. We have generated polyclonal and monoclonal antibodies that detect merlin as an approximately 66 kD protein in many different cell types. Using indirect immunofluorescence we have for the first time visualized endogenous merlin and localized it to the motile regions, such as leading or ruffling edges, in human fibroblast and meningioma cells. Merlin co-localizes with F-actin in these motile regions but is not associated with stress fibers. Merlin does not localize to the same structures as either ezrin or moesin in human meningioma cells, suggesting a function distinct from these ERMs. Thus, merlin is associated with motile regions of the cell and its participation in these structures may be intimately involved in control of proliferation in Schwann cells and meningeal cells.

Neurofibromatosis 2 (NF2) is an autosomal dominant disease characterized by bilateral vestibular schwannomas and other nonmalignant tumors of the brain, spinal cord, and peripheral nerves. Although the average age of onset of NF2 is 20 years, some individuals may become symptomatic in childhood. We studied 5 unrelated NF2 patients who became symptomatic before age 13. All 5 had multiple tumors in addition to vestibular schwannoma, and none had a positive family history. Sequence analysis of the NF2 gene revealed identical nonsense mutation of exon 6 in 3 patients. Because this mutation destroys a restriction enzyme recognition site, genomic DNA from the 2 other children was directly tested for this change and identical alterations were detected. Although the work of our laboratory and others has not, in general, detected identical mutations in unrelated patients, this mutation seems to occur particularly frequently in the pediatric population and thus may be associated with an especially severe phenotype. Restriction analysis in children with NF2 may be a cost effective way of identifying their mutation. Further work is needed to characterize the effects of this change on the NF2 protein product and its relationship to this severe phenotype.

The actions of the neurotransmitter adenosine are mediated by a family of high-affinity, G protein-coupled receptors. We have characterized the gene for the human A2a subtype of adenosine receptor (hA2aR) and determined levels of A2aR mRNA in human brain regions and nonneural tissues. Human genomic Southern blot analysis demonstrates the presence of a single gene encoding the hA2aR located on chromosome 22. Two overlapping cosmids containing the hA2aR gene were isolated from a chromosome 22 library and characterized. Southern blot and sequence analyses demonstrate that the hA2aR gene spans approximately 9-10 kb with a single intron interrupting the coding sequence between the regions encoding transmembrane domains III and IV. The sequence of the hA2aR gene diverged from the reported cDNA structure in the 5' untranslated region. This divergence appears to result from an artifact in the construction of the original cDNA library. By northern blot analysis, high expression of the hA2aR gene was identified in the caudate nucleus with low levels of expression in other brain regions. High expression was also seen in immune tissues; lesser A2aR expression was detected in heart and lung. The gene for the A2a subtype of receptor for the neurotransmitter adenosine falls in the class of intron containing G protein-coupled receptor genes. Expression in the basal ganglia is consistent with a role for the hA2aR in motor control. Activation of the A2aR may also regulate immune responses and cardiopulmonary function.