Understanding type and quality of relationships between individuals with chromosome 18 syndromes and their siblings.

Siblings of individuals with disabilities hold a pivotal and sometimes unappreciated position in the lives of their brother or sister. We sought to understand the unique challenges and opportunities in relationships between children with chromosome 18 conditions and their siblings and to identify the ways to support this relationship. Participants were recruited through the lay advocacy organization, the Chromosome 18 Registry & Research Society. Fifty-seven siblings from 36 families participated, using an investigator designed instrument, were asked to agree or disagreed with statements from four content areas (information and knowledge about the syndrome, feelings about the sibling relationship, involvement with and caregiving for their sibling, and support and advocacy). Siblings reported that they know their sibling with a disability very well and reported a wide range of emotions regarding their sibling. There was a strong sense of pride in their brother/sister's abilities, and many participants reported attempts to help others understand their brother/sister. Many siblings reported a dislike for the common assumption that their affected sibling is a burden on the family. Most participants reported feeling some degree of responsibility for their affected sibling, but many also reported that they enjoy this role. Sixty-three parents from 36 families responded to the survey. Most parents felt their typically developing children enjoyed teaching new things to their affected child as well as being a good role model for them. Most parents also felt their typically developing child was comfortable telling others about their sibling's condition. Recommendations for interventions and future research are discussed.

Frequency and circumstances of falls for people with Charcot-Marie-Tooth disease: A cross sectional survey.

OBJECTIVE: People with Charcot-Marie-Tooth (CMT) disease may be at risk of falls due to distal muscle weakness and sensory impairment. We aimed to understand the frequency of falls in a cohort, where they occurred, injury and to what people attributed the possible cause. DESIGN: A cross-sectional survey design was used. It was sent by post to ascertain the frequency of falls and near falls, plus the circumstances of the last three falls events they could recall. SETTING: The survey was administered to 252 people with CMT who were patients at a specialist neuromuscular centre. PARTICIPANTS: People were approached who had a clinical diagnosis by a neuromuscular specialist neurologist. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: The Falls Event Questionnaire. RESULTS: Responses were received from 107 people with CMT. Falls and near falls were reported by 86% of survey respondents. The majority of falls occurred at home, and muscular weakness appeared to be blamed the most, with participants describing tripping due to foot drop or joints giving way. A similar pattern was observed for near falls, but they tended to be more frequent. Moderate and major injuries were relatively rare, with the majority of falls resulting in scrapes and bruises or the faller feeling shaken by the experience. DISCUSSION: The impact of falls is far reaching, in terms of injury risk and the consequences of the fear of falling. Interventions to improve balance and reduce falls are an important rehabilitation focus for people with CMT.

Consequences of chromsome18q deletions.

Providing clinically relevant prognoses and treatment information for people with a chromsome18q deletion is particularly challenging because every unrelated person has a unique region of hemizygosity. The hemizygous region can involve almost any region of 18q including between 1 and 101 genes (30 Mb of DNA). Most individuals have terminal deletions, but in our cohort of over 350 individuals 23% have interstitial deletions. Because of this heterogeneity, we take a gene by gene approach to understanding the clinical consequences. There are 196 genes on 18q. We classified 133 of them as dosage insensitive, 15 (8%) as dosage sensitive leading to haploinsufficiency while another 10 (5%) have effects that are conditionally haploinsufficient and are dependent on another factor, genetic or environmental in order to cause an abnormal phenotype. Thirty-seven genes (19%) have insufficient information to classify their dosage effect. Phenotypes attributed to single genes include: congenital heart disease, minor bone morphology changes, central nervous system dysmyelination, expressive speech delay, vesicouretreral reflux, polyposis, Pitt-Hopkins syndrome, intellectual disability, executive function impairment, male infertility, aural atresia, and high frequency sensorineural hearing loss. Additionally, identified critical regions for other phenotypes include: adolescent idiopathic scoliosis and pectus excavatum, Virchow-Robin perivascular spaces, small corpus callosum, strabismus, atopic disorders, mood disorder, IgA deficiency, nystagmus, congenital heart disease, kidney malformation, vertical talus, CNS dysmyelination growth hormone deficiency and cleft palate. Together these findings make it increasingly feasible to compile an individualized syndrome description based on each person's individuated genotype. Future work will focus on understanding molecular mechanisms leading to treatment.

A review of 18p deletions.

Since 18p- was first described in 1963, much progress has been made in our understanding of this classic deletion condition. We have been able to establish a fairly complete picture of the phenotype when the deletion breakpoint occurs at the centromere, and we are working to establish the phenotypic effects when each gene on 18p is hemizygous. Our aim is to provide genotype-specific anticipatory guidance and recommendations to families with an 18p- diagnosis. In addition, establishing the molecular underpinnings of the condition will potentially suggest targets for molecular treatments. Thus, the next step is to establish the precise effects of specific gene deletions. As we look forward to deepening our understanding of 18p-, our focus will continue to be on the establishment of robust genotype-phenotype correlations and the penetrance of these phenotypes. We will continue to follow our 18p- cohort closely as they age to determine the presence or absence of some of these diagnoses, including spinocerebellar ataxia (SCA), facioscapulohumeral muscular dystrophy (FSHD), and dystonia. We will also continue to refine the critical regions for other phenotypes as we enroll additional (hopefully informative) participants into the research study and as the mechanisms of the genes in these regions are elucidated. Mouse models will also be developed to further our understanding of the effects of hemizygosity as well as to serve as models for treatment development.

Tetrasomy 18p: report of cognitive and behavioral characteristics.

Our purpose was to describe intellectual and behavioral characteristics of persons with tetrasomy 18p. This is a more detailed investigation into the cognitive and behavioral characteristics of our previously reported tetrasomy 18p cohort of 43 plus six additional participants. We evaluated the intellectual functioning using standard measures of cognitive ability, measures of executive functioning, adaptive and maladaptive behaviors. Intellectual abilities ranged from mild impairment/borderline normal to severe/profound impairment calling into question the assumption that severe cognitive limitation is always a feature of tetrasomy 18p. For persons with tetrasomy 18p with mild cognitive deficits, the main barriers to successful functioning stems from limited social and metacognitive skill development and behavior regulation problems rather than being solely determined by cognitive deficits alone.

Whole arm deletions of 18p: medical and developmental effects.

Deletions of the short arm of chromosome 18 have been well-described in case reports. However, the utility of these descriptions in clinical practice is limited by varied and imprecise breakpoints. As we work to establish genotype-phenotype correlations for 18p-, it is critical to have accurate and complete clinical descriptions of individuals with differing breakpoints. In addition, the developmental profile of 18p- has not been well-delineated. We undertook a thorough review of the medical histories of 31 individuals with 18p- and a breakpoint in the centromeric region. We collected developmental data using mailed surveys and questionnaires. The most common findings included neonatal complications; cardiac anomalies; hypotonia; MRI abnormalities; endocrine dysfunction; strabismus; ptosis; and refractive errors. Less common features included holoprosencephaly and its microforms; hearing loss; and orthopedic anomalies. The developmental effects of the deletion appear to be less severe than reported in the literature, as average IQ scores were in the range of borderline intellectual functioning. Based on responses to standardized questionnaires, it appears this population has marked difficulty with activities of daily living, though several young adults were able to live independent of their parents. This manuscript represents the most comprehensive description of a cohort of 18p- individuals with identical breakpoints. Despite identical breakpoints, a great deal of phenotype variability remained among this population, suggesting that many of the genes on 18p- cause low-penetrance phenotypes when present in a hemizygous state. Future efforts will focus on the clinical description of individuals with more distal breakpoints and the identification of critical regions and candidate genes.

Adults with Chromosome 18 Abnormalities.

The identification of an underlying chromosome abnormality frequently marks the endpoint of a diagnostic odyssey. However, families are frequently left with more questions than answers as they consider their child's future. In the case of rare chromosome conditions, a lack of longitudinal data often makes it difficult to provide anticipatory guidance to these families. The objective of this study is to describe the lifespan, educational attainment, living situation, and behavioral phenotype of adults with chromosome 18 abnormalities. The Chromosome 18 Clinical Research Center has enrolled 483 individuals with one of the following conditions: 18q-, 18p-, Tetrasomy 18p, and Ring 18. As a part of the ongoing longitudinal study, we collect data on living arrangements, educational level attained, and employment status as well as data on executive functioning and behavioral skills on an annual basis. Within our cohort, 28 of the 483 participants have died, the majority of whom have deletions encompassing the TCF4 gene or who have unbalanced rearrangement involving other chromosomes. Data regarding the cause of and age at death are presented. We also report on the living situation, educational attainment, and behavioral phenotype of the 151 participants over the age of 18. In general, educational level is higher for people with all these conditions than implied by the early literature, including some that received post-high school education. In addition, some individuals are able to live independently, though at this point they represent a minority of patients. Data on executive function and behavioral phenotype are also presented. Taken together, these data provide insight into the long-term outcome for individuals with a chromosome 18 condition. This information is critical in counseling families on the range of potential outcomes for their child.

Establishing a reference group for distal 18q-: clinical description and molecular basis.

Although constitutional chromosome abnormalities have been recognized since the 1960s, clinical characterization and development of treatment options have been hampered by their obvious genetic complexity and relative rarity. Additionally, deletions of 18q are particularly heterogeneous, with no two people having the same breakpoints. We identified 16 individuals with deletions that, despite unique breakpoints, encompass the same set of genes within a 17.6-Mb region. This group represents the most genotypically similar group yet identified with distal 18q deletions. As the deletion is of average size when compared with other 18q deletions, this group can serve as a reference point for the clinical and molecular description of this condition. We performed a thorough medical record review as well as a series of clinical evaluations on 14 of the 16 individuals. Common functional findings included developmental delays, hypotonia, growth hormone deficiency, and hearing loss. Structural anomalies included foot anomalies, ear canal atresia/stenosis, and hypospadias. The majority of individuals performed within the low normal range of cognitive ability but had more serious deficits in adaptive abilities. Of interest, the hemizygous region contains 38 known genes, 26 of which are sufficiently understood to tentatively determine dosage sensitivity. Published data suggest that 20 are unlikely to cause an abnormal phenotype in the hemizygous state and five are likely to be dosage sensitive: TNX3, NETO1, ZNF407, TSHZ1, and NFATC. A sixth gene, ATP9B, may be conditionally dosage sensitive. Not all distal 18q- phenotypes can be attributed to these six genes; however, this is an important advance in the molecular characterization of 18q deletions.

Cortical Volume Alterations in Conduct Disordered Adolescents with and without Bipolar Disorder.

BACKGROUND: There is increasing evidence that bipolar disorder (BD) and conduct disorder (CD) are co-occurring disorders. Magnetic resonance imaging has revealed differences in the structure and function of the frontal cortex in these disorders when studied separately; however, the impact of BD comorbidity on brain structure in adolescents with CD has not yet been examined. METHOD: We conducted an optimized voxel based morphometry (VBM) study of juvenile offenders with the following diagnoses: conduct disorder with comorbid bipolar disorder (CD-BD; n = 24), conduct disorder without bipolar disorder (CD; n = 24) and healthy controls (HC, n = 24). Participants were 13-17 years of age, in a residential treatment facility for repeat offenders. The three groups in this study were similar in age, gender, socioeconomic status and ethnicity. RESULTS: We found CD-BD subjects had decreased volume relative to controls at the voxel level in the right medial prefrontal cortex (PFC). Using a Threshold-Free Cluster Enhancement (TFCE) technique, the CD-BD subjects had significantly decreased volumes of the right medial prefrontal cortex and portions of the superior and inferior frontal gyrus, anterior cingulate and temporal gyrus. The CD subjects did not have differences in brain volume compared to control subjects or CD-BD subjects. CONCLUSIONS: Our findings suggest the comorbidity between CD and BD is associated with neurobiological impact namely volumetric differences from healthy controls. Furthermore subjects with this comorbidity had poorer lifetime functioning, more mood and attentional dysfunction, and more medication exposure than subjects with CD who were not BD.

Mood disorders in individuals with distal 18q deletions.

We examined 36 participants at least 4 years old with hemizygous distal deletions of the long arm of Chromosome 18 (18q-) for histories of mood disorders and to characterize these disorders clinically. Since each participant had a different region of 18q hemizygosity, our goal was also to identify their common region of hemizygosity associated with mood disorders; thereby identifying candidate causal genes in that region. Lifetime mood and other psychiatric disorders were determined by semi-structured interviews of patients and parents, supplemented by reviews of medical and psychiatric records, and norm-referenced psychological assessment instruments, for psychiatric symptoms, cognitive problems, and adaptive functioning. Sixteen participants were identified with lifetime mood disorders (ages 12-42 years, 71% female, 14 having had unipolar depression and 2 with bipolar disorders). From the group of 20 who did not meet criteria for a mood disorder; a comparison group of 6 participants were identified who were matched for age range and deletion size. Mood-disordered patients had high rates of anxiety (75%) and externalizing behavior disorders (44%), and significant mean differences from comparison patients (P < 0.05), including higher overall and verbal IQs and lower autistic symptoms. A critical region was defined in the mood-disordered group that included a hypothetical gene, C18orf62, and two known genes, ZADH2 and TSHZ1. We conclude that patients having terminal deletions of this critical region of the long arm of Chromosome 18 are highly likely to have mood disorders, which are often comorbid with anxiety and to a lesser extent with externalizing disorders.

Improving student comfort with death and dying discussions through facilitated family encounters.

OBJECTIVE: The purpose of this study was to explore the educational potential for a collaboration between palliative medicine and psychiatry designed to improve first-year medical students' knowledge and comfort with end-of-life issues through a facilitated small-group discussion with family members of recently-deceased loved ones. METHODS: A group of 222 first-year medical students were divided into 14 small groups. Each group also consisted of two mental-health providers, one palliative-medicine interdisciplinary team member, and one family member of a recently-deceased hospice patient. A death-and-dying discussion between students and family members was facilitated by the mental-health and palliative-medicine faculty and was followed by post-activity evaluations. RESULTS: As a result of the facilitated activity, 77% of participants reported increased comfort levels and 85% reported improved knowledge of end-of-life issues. Students reporting benefit were more likely to perceive higher facilitator and family comfort levels with end-of-life discussions, better activity organization, and utility of post-encounter group discussion. CONCLUSIONS: Facilitated conversations between students and family members of recently-deceased loved ones may improve comfort and knowledge with end-of-life conversations. Future studies should explore the longer-range impact of this educational activity.

The role of the TCF4 gene in the phenotype of individuals with 18q segmental deletions.

The goal of this study is to define the effects of TCF4 hemizygosity in the context of a larger segmental deletion of chromosome 18q. Our cohort included 37 individuals with deletions of 18q. Twenty-seven had deletions including TCF4 (TCF4 (+/-)); nine had deletions that did not include TCF4 (TCF4 (+/+)); and one individual had a microdeletion that included only the TCF4 gene. We compared phenotypic data from the participants' medical records, survey responses, and in-person evaluations. Features unique to the TCF4 (+/-) individuals included abnormal corpus callosum, short neck, small penis, accessory and wide-spaced nipples, broad or clubbed fingers, and sacral dimple. The developmental data revealed that TCF4 (+/+) individuals were only moderately developmentally delayed while TCF4 (+/-) individuals failed to reach developmental milestones beyond those typically acquired by 12 months of age. TCF4 hemizygosity also conferred an increased risk of early death principally due to aspiration-related complications. Hemizygosity for TCF4 confers a significant impact primarily with regard to cognitive and motor development, resulting in a very different prognosis for individuals hemizygous for TCF4 when compared to individuals hemizygous for other regions of distal 18q.

Tetrasomy 18p: report of the molecular and clinical findings of 43 individuals.

Thus far, the phenotype of tetrasomy 18p has been primarily delineated by published case series and reports. Findings reported in more than 25% of these cases include neonatal feeding problems, growth retardation, microcephaly, strabismus, muscle tone abnormalities, scoliosis/kyphosis, and variants on brain MRI. Developmental delays and cognitive impairment are universally present. The purpose of this study was to more fully describe tetrasomy 18p at both the genotypic and the phenotypic levels. Array CGH was performed on 43 samples from individuals with tetrasomy 18p diagnosed via routine karyotype. The medical records of 42 of these 43 individuals were reviewed. In order to gain additional phenotypic data, 31 individuals with tetrasomy 18p underwent a series of clinical evaluations at the Chromosome 18 Clinical Research Center. Results from the molecular analysis indicated that 42 of 43 samples analyzed had 4 copies of the entire p arm of chromosome 18; one individual was also trisomic for a section of proximal 18q. The results of the medical records review and clinical evaluations expand the phenotypic description of tetrasomy 18p to include neonatal jaundice and respiratory distress; recurrent otitis media; hearing loss; seizures; refractive errors; constipation and gastroesophageal reflux; cryptorchidism; heart defects; and foot anomalies. Additional findings identified in a small number of individuals include hernias, myelomeningocele, kidney defects, short stature, and failure to respond to growth hormone stimulation testing. Additionally, a profile of dysmorphic features is described. Lastly, a series of clinical evaluations to be considered for individuals with tetrasomy 18p is suggested.

Genetic determinants of autism in individuals with deletions of 18q.

Previous research has suggested that individuals with constitutional hemizygosity of 18q have a higher risk of autistic-like behaviors. We sought to identify genomic factors located on chromosome 18 as well as other loci that correlate with autistic behaviors. One hundred and five individuals with 18q- were assessed by high-resolution oligo aCGH and by parental ratings of behavior on the Gilliam Autism Rating Scale. Forty-five individuals (43%) had scores within the "possibly" or "very likely" categories of risk for an autism diagnosis. We searched for genetic determinants of autism by (1) identifying additional chromosome copy number changes (2) Identifying common regions of hemizygosity on 18q, and (3) evaluating four regions containing candidate genes located on 18q (MBD1, TCF4, NETO1, FBXO15). Three individuals with a "very likely" probability of autism had a captured 17p telomere in addition to the 18q deletion suggesting a possible synergy between hemizygosity of 18q and trigosity of 17p. In addition, two of the individuals with an 18q deletion and a "very likely" probability of autism rating had a duplication of the entire short arm of chromosome 18. Although no common region of hemizygosity on 18q was identified, analysis of four regions containing candidate genes suggested that individuals were significantly more likely to exhibit autistic-like behaviors if their region of hemizygosity included TCF4, NETO1, and FBXO15 than if they had any other combination of hemizygosity of the candidate genes. Taken together, these findings identify several new potential candidate genes or regions for autistic behaviors.

Quantifying asthma symptoms in adults: the Lara Asthma Symptom Scale.

BACKGROUND: Accurate assessment of asthma symptoms is critical in research and clinical settings. A multidimensional asthma control questionnaire could provide more accurate information about asthma symptoms than global assessments, which often overestimate asthma control. OBJECTIVE: We sought to evaluate the efficacy of the Lara Asthma Symptom Scale (LASS) in adults with persistent asthma. METHODS: Participants were 18 to 64 years of age with persistent asthma. Data were collected at baseline, 6 months, and 12 months. We described the construct and predictive validity of the LASS by comparing it with measures of pulmonary function (FEV(1)), asthma-specific quality of life (Juniper's Asthma Quality of Life Questionnaire [AQLQ]), and health care use (emergency department [ED] visits and hospitalizations). RESULTS: Three hundred eighty-three participants provided baseline data. The LASS had high internal consistency reliability (Cronbach alpha = .84). LASS scores correlated significantly with baseline measures of FEV(1) (-0.20, P = .0002), AQLQ (-0.68, P < .0001), ED visits (0.17, P = .002), and hospitalizations (0.15, P = .008). Baseline LASS scores were associated significantly with ED visits (P = .03) and hospitalizations (P = .04) over the subsequent 12 months. Change in LASS scores over time correlated significantly with changes in FEV(1) (-0.22, P = .001) and AQLQ (-0.70, P < .001). CONCLUSIONS: The LASS demonstrated good internal consistency, excellent validity based on concurrent criterion validity and longitudinal predictive validity, and good discriminatory properties in a heterogeneous sample of adults with persistent asthma. CLINICAL IMPLICATIONS: This study validates a simple multidimensional asthma questionnaire as a clinical tool in the assessment of asthma control in adults.

Neuropsychological deficits in adolescents with conduct disorder and comorbid bipolar disorder: a pilot study.

OBJECTIVE: We report pilot data on neuropsychological deficits in aggressive juvenile offenders with and without bipolar disorder compared with each other and healthy controls. METHOD: We assessed 52 adolescents and their parent or guardians: 36 incarcerated juvenile offenders and 16 community controls using the Schedule for Affective Disorders and Schizophrenia for School Age Children, Present and Life-Time Version and a neuropsychological testing battery. All incarcerated subjects (n=34) met criteria for Conduct Disorder (CD); 26 are classified as Non-BD-CD, and eight with CD and Bipolar disorder (CD-BD). These subjects were compared to community controls (n=16) matched for age, gender, SES and ethnicity. RESULTS: Relative to controls, the Non-BD-CD subjects' impairments (p<0.05) were in cognitive ability, set shifting/inhibition, planning and verbal memory-language functioning. The CD-BD group displayed impairments (p<0.05) relative to controls in cognitive ability, set shifting, verbal memory-language functioning, and visuospatial tasks. The Non-BD-CD and CD-BD groups however did not display significant differences on most neuropsychological measures compared with each other. When we controlled for Attention Deficit Hyperactivity Disorder, the Non-CD-BP subjects continued to show deficits on Verbal measures where the CD-BD subjects maintained deficits in measures of cognitive ability, verbal measures and visual spatial tests. CONCLUSIONS: Juvenile offender with CD displayed a wide range of deficits on neuropsychological testing compared with controls. Although juvenile offenders with and without BD differed on their clinical presentation, differences on neuropsychological measures are not specific and may be related to comorbid diagnoses.