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Pollak RM, Burrell TL, Cubells JF, Klaiman C, Murphy MM, Saulnier CA, Walker EF, White SP, Mulle JG. Adaptive behaviour deficits in individuals with 3q29 deletion syndrome. J Intellect Disabil Res 2024; 68:113-127. [PMID: 37740553 PMCID: PMC10843465 DOI: 10.1111/jir.13094] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 06/28/2023] [Accepted: 09/02/2023] [Indexed: 09/24/2023]
Abstract
BACKGROUND 3q29 deletion syndrome (3q29del) is associated with a significantly increased risk for neurodevelopmental and neuropsychiatric phenotypes. Mild to moderate intellectual disability (ID) is common in this population, and previous work by our team identified substantial deficits in adaptive behaviour. However, the full profile of adaptive function in 3q29del has not been described nor has it been compared with other genomic syndromes associated with elevated risk for neurodevelopmental and neuropsychiatric phenotypes. METHODS Individuals with 3q29del (n = 32, 62.5% male) were evaluated using the Vineland Adaptive Behaviour Scales, Third Edition, Comprehensive Parent/Caregiver Form (Vineland-3). We explored the relationship between adaptive behaviour and cognitive function, executive function, and neurodevelopmental and neuropsychiatric comorbidities in our 3q29del study sample, and we compared subjects with 3q29del with published data on fragile X syndrome, 22q11.2 deletion syndrome and 16p11.2 deletion and duplication syndromes. RESULTS Individuals with 3q29del had global deficits in adaptive behaviour that were not driven by specific weaknesses in any given domain. Individual neurodevelopmental and neuropsychiatric diagnoses had a small effect on adaptive behaviour, and the cumulative number of comorbid diagnoses was significantly negatively associated with Vineland-3 performance. Both cognitive ability and executive function were significantly associated with adaptive behaviour, and executive function was a better predictor of Vineland-3 performance than cognitive ability. Finally, the severity of adaptive behaviour deficits in 3q29del was distinct from previously published data on comparable genomic disorders. CONCLUSIONS Individuals with 3q29del have significant deficits in adaptive behaviour, affecting all domains assessed by the Vineland-3. Executive function is a better predictor of adaptive behaviour than cognitive ability in this population and suggests that interventions targeting executive function may be an effective therapeutic strategy.
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Affiliation(s)
- R M Pollak
- Center for Advanced Biotechnology and Medicine, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ, USA
| | - T L Burrell
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA, USA
| | - J F Cubells
- Department of Human Genetics, School of Medicine, Emory University, Atlanta, GA, USA
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Emory University, Atlanta, GA, USA
| | - C Klaiman
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA, USA
- Marcus Autism Center, Children's Healthcare of Atlanta and Emory University, Atlanta, GA, USA
| | - M M Murphy
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA, USA
| | - C A Saulnier
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA, USA
- Neurodevelopmental Assessment & Consulting Services, Atlanta, GA, USA
| | - E F Walker
- Department of Psychology, Emory University, Atlanta, GA, USA
| | - S P White
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA, USA
- Marcus Autism Center, Children's Healthcare of Atlanta and Emory University, Atlanta, GA, USA
| | - J G Mulle
- Center for Advanced Biotechnology and Medicine, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ, USA
- Department of Psychiatry, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ, USA
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Klaiman C, White SP, Saulnier C, Murphy M, Burrell L, Cubells J, Walker E, Mulle JG. A distinct cognitive profile in individuals with 3q29 deletion syndrome. J Intellect Disabil Res 2023; 67:216-227. [PMID: 35297118 DOI: 10.1111/jir.12919] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 01/18/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND 3q29 deletion syndrome is associated with mild to moderate intellectual disability as well as comorbid psychopathology such as ADHD, anxiety, ASD and schizophrenia. A greater understanding of specific profiles that could increase risk for psychopathology is necessary in order to best understand and support individuals with 3q29 deletion syndrome. The goal of this study was to thus carefully outline the strengths and weaknesses of these individuals. A second goal was to ask whether the cognitive impact of the deletion predicted psychopathology in other domains. METHODS We systematically evaluated cognitive ability, adaptive behaviour and psychopathology in 32 individuals with the canonical 3q29 deletion using gold-standard instruments and a standardised phenotyping protocol. RESULTS Mean full scale IQ was 73 (range 40-99). Verbal subtest score (mean 80, range 31-106) was slightly higher and had a greater range than non-verbal subtest score (mean 75, range 53-98). Spatial ability was evaluated in a subset (n = 24) and was lower than verbal and non-verbal ability (mean 71, range 34-108). There was an average 14-point difference between verbal and non-verbal subset scores; 60% of the time the verbal subset score was higher than the non-verbal subset score. Study subjects with a verbal ability subtest score lower than the non-verbal subtest score were four times more likely to have a diagnosis of intellectual disability (suggestive, P value 0.07). The age at which a child first spoke two-word phrases was strongly associated with measures of verbal ability (P value 2.56e-07). Cognitive ability was correlated with adaptive behaviour measures (correlation 0.42, P value 0.02). However, although group means found equivalent scores, there was, on average, a 10-point gap between these skills (range -33 to 33), in either direction, in about 50% of the sample, suggesting that cognitive measures only partially inform adaptive ability. Cognitive ability scores did not have any significant relationship to cumulative burden of psychopathology nor to individual neurodevelopmental or psychiatric diagnoses. CONCLUSIONS Individuals with 3q29 deletion syndrome have a complex pattern of cognitive disability. Two-thirds of individuals with the deletion will exhibit significant strength in verbal ability; this may mask deficits in non-verbal reasoning, leading to an overestimation of overall ability. Deficits in verbal ability may be the driver of intellectual disability diagnosis. Cognitive ability is not a strong indicator of other neurodevelopmental or psychiatric impairment; thus, individuals with 3q29 deletion syndrome who exhibit IQ scores within the normal range should receive all recommended behavioural evaluations.
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Affiliation(s)
- C Klaiman
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA, USA
- Marcus Autism Center, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, GA, USA
| | - S P White
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA, USA
- Marcus Autism Center, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, GA, USA
| | - C Saulnier
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA, USA
- Neurodevelopmental Assessment & Consulting Services, Atlanta, GA, USA
| | - M Murphy
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
| | - L Burrell
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA, USA
- Marcus Autism Center, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, GA, USA
| | - J Cubells
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
- Department of Psychiatry and Behavioral Science, Emory University School of Medicine, Atlanta, GA, USA
| | - E Walker
- Department of Psychology, Emory University, Atlanta, GA, USA
| | - J G Mulle
- Department of Psychiatry, Robert Wood Johnson School of Medicine, Rutgers University, Piscataway, New Jersey, USA
- Center for Advanced Biotechnology and Medicine, Robert Wood Johnson School of Medicine, Rutgers University, Piscataway, New Jersey, USA
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Mulle JG, Sullivan PF, Hjerling-Leffler J. Editorial overview: Rare CNV disorders and neuropsychiatric phenotypes: opportunities, challenges, solutions. Curr Opin Genet Dev 2021; 68:iii-ix. [PMID: 34059379 PMCID: PMC8722467 DOI: 10.1016/j.gde.2021.05.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Jennifer Gladys Mulle
- Department of Human Genetics, Emory University School of Medicine, Atlanta GA 30322, United States.
| | - Patrick F Sullivan
- Departments of Genetics and Psychiatry, University of North Carolina, Chapel Hill, NC, United States; Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
| | - Jens Hjerling-Leffler
- Laboratory of Molecular Neurobiology, Department Medical Biochemistry and Biophysics, Karolinska Institutet, SE-17177 Stockholm, Sweden.
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Mak BC, Sanchez Russo R, Gambello MJ, Fleischer N, Black ED, Leslie E, Murphy MM, Mulle JG. Craniofacial features of 3q29 deletion syndrome: Application of next-generation phenotyping technology. Am J Med Genet A 2021; 185:2094-2101. [PMID: 33938623 PMCID: PMC8250870 DOI: 10.1002/ajmg.a.62227] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 03/23/2021] [Accepted: 03/27/2021] [Indexed: 12/21/2022]
Abstract
3q29 deletion syndrome (3q29del) is a recurrent deletion syndrome associated with neuropsychiatric disorders and congenital anomalies. Dysmorphic facial features have been described but not systematically characterized. This study aims to detail the 3q29del craniofacial phenotype and use a machine learning approach to categorize individuals with 3q29del through analysis of 2D photos. Detailed dysmorphology exam and 2D facial photos were ascertained from 31 individuals with 3q29del. Photos were used to train the next-generation phenotyping algorithm DeepGestalt (Face2Gene by FDNA, Inc, Boston, MA) to distinguish 3q29del cases from controls and all other recognized syndromes. Area under the curve of receiver operating characteristic curves (AUC-ROC) was used to determine the capacity of Face2Gene to identify 3q29del cases against controls. In this cohort, the most common observed craniofacial features were prominent forehead (48.4%), prominent nose tip (35.5%), and thin upper lip vermillion (25.8%). The FDNA technology showed an ability to distinguish cases from controls with an AUC-ROC value of 0.873 (p = 0.006) and led to the inclusion of 3q29del as one of the supported syndromes. This study found a recognizable facial pattern in 3q29del, as observed by trained clinical geneticists and next-generation phenotyping technology. These results expand the potential application of automated technology such as FDNA in identifying rare genetic syndromes, even when facial dysmorphology is subtle.
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Affiliation(s)
- Bryan C Mak
- Department of Human Genetics, Emory University School, of Medicine, Atlanta, Georgia, USA
| | - Rossana Sanchez Russo
- Department of Human Genetics, Emory University School, of Medicine, Atlanta, Georgia, USA
| | - Michael J Gambello
- Department of Human Genetics, Emory University School, of Medicine, Atlanta, Georgia, USA.,Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA
| | | | - Emily D Black
- Department of Human Genetics, Emory University School, of Medicine, Atlanta, Georgia, USA
| | - Elizabeth Leslie
- Department of Human Genetics, Emory University School, of Medicine, Atlanta, Georgia, USA
| | - Melissa M Murphy
- Department of Human Genetics, Emory University School, of Medicine, Atlanta, Georgia, USA
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- Department of Human Genetics, Emory University School, of Medicine, Atlanta, Georgia, USA
| | - Jennifer Gladys Mulle
- Department of Human Genetics, Emory University School, of Medicine, Atlanta, Georgia, USA.,Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
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5
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Sanchez Russo R, Gambello MJ, Murphy MM, Aberizk K, Black E, Burrell TL, Carlock G, Cubells JF, Epstein MT, Espana R, Goines K, Guest RM, Klaiman C, Koh S, Leslie EJ, Li L, Novacek DM, Saulnier CA, Sefik E, Shultz S, Walker E, White SP, Mulle JG. Deep phenotyping in 3q29 deletion syndrome: recommendations for clinical care. Genet Med 2021; 23:872-880. [PMID: 33564151 PMCID: PMC8105170 DOI: 10.1038/s41436-020-01053-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Revised: 11/20/2020] [Accepted: 11/20/2020] [Indexed: 11/09/2022] Open
Abstract
PURPOSE To understand the consequences of the 3q29 deletion on medical, neurodevelopmental, psychiatric, brain structural, and neurological sequalae by systematic evaluation of affected individuals. To develop evidence-based recommendations using these data for effective clinical care. METHODS Thirty-two individuals with the 3q29 deletion were evaluated using a defined phenotyping protocol and standardized data collection instruments. RESULTS Medical manifestations were varied and reported across nearly every organ system. The most severe manifestations were congenital heart defects (25%) and the most common were gastrointestinal symptoms (81%). Physical examination revealed a high proportion of musculoskeletal findings (81%). Neurodevelopmental phenotypes represent a significant burden and include intellectual disability (34%), autism spectrum disorder (38%), executive function deficits (46%), and graphomotor weakness (78%). Psychiatric illness manifests across the lifespan with psychosis prodrome (15%), psychosis (20%), anxiety disorders (40%), and attention deficit-hyperactivity disorder (ADHD) (63%). Neuroimaging revealed structural anomalies of the posterior fossa, but on neurological exam study subjects displayed only mild or moderate motor vulnerabilities. CONCLUSION By direct evaluation of 3q29 deletion study subjects, we document common features of the syndrome, including a high burden of neurodevelopmental and neuropsychiatric phenotypes. Evidence-based recommendations for evaluation, referral, and management are provided to help guide clinicians in the care of 3q29 deletion patients.
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Affiliation(s)
| | - Michael J Gambello
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
| | - Melissa M Murphy
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
| | - Katrina Aberizk
- Department of Psychology, Emory University, Atlanta, GA, USA
| | - Emily Black
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
| | - T Lindsey Burrell
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
- Marcus Autism Center, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, GA, USA
| | - Grace Carlock
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
| | - Joseph F Cubells
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
- Department of Psychiatry and Behavioral Science, Emory University School of Medicine, Atlanta, GA, USA
| | - Michael T Epstein
- Department of Psychiatry and Behavioral Science, Emory University School of Medicine, Atlanta, GA, USA
| | - Roberto Espana
- Department of Psychology, Emory University, Atlanta, GA, USA
| | - Katrina Goines
- Department of Psychology, Emory University, Atlanta, GA, USA
| | - Ryan M Guest
- Department of Psychology, Emory University, Atlanta, GA, USA
| | - Cheryl Klaiman
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
- Marcus Autism Center, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, GA, USA
| | - Sookyong Koh
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| | - Elizabeth J Leslie
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
| | - Longchuan Li
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
- Marcus Autism Center, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, GA, USA
| | - Derek M Novacek
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, CA, USA
- Desert Pacific Mental Illness, Research, Education, and Clinical Center, VA Greater Los Angeles Healthcare System, Los Angeles, CA, USA
| | - Celine A Saulnier
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
- Neurodevelopmental Assessment & Consulting Services, Atlanta, GA, USA
| | - Esra Sefik
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
- Department of Psychology, Emory University, Atlanta, GA, USA
| | - Sarah Shultz
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
- Marcus Autism Center, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, GA, USA
| | - Elaine Walker
- Department of Psychology, Emory University, Atlanta, GA, USA
| | - Stormi Pulver White
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
- Marcus Autism Center, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, GA, USA
| | - Jennifer Gladys Mulle
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA.
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA.
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Rutkowski TP, Purcell RH, Pollak RM, Grewenow SM, Gafford GM, Malone T, Khan UA, Schroeder JP, Epstein MP, Bassell GJ, Warren ST, Weinshenker D, Caspary T, Mulle JG. Behavioral changes and growth deficits in a CRISPR engineered mouse model of the schizophrenia-associated 3q29 deletion. Mol Psychiatry 2021; 26:772-783. [PMID: 30976085 PMCID: PMC6788962 DOI: 10.1038/s41380-019-0413-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 02/13/2019] [Accepted: 03/18/2019] [Indexed: 12/27/2022]
Abstract
The 3q29 deletion confers increased risk for neuropsychiatric phenotypes including intellectual disability, autism spectrum disorder, generalized anxiety disorder, and a >40-fold increased risk for schizophrenia. To investigate consequences of the 3q29 deletion in an experimental system, we used CRISPR/Cas9 technology to introduce a heterozygous deletion into the syntenic interval on C57BL/6 mouse chromosome 16. mRNA abundance for 20 of the 21 genes in the interval was reduced by ~50%, while protein levels were reduced for only a subset of these, suggesting a compensatory mechanism. Mice harboring the deletion manifested behavioral impairments in multiple domains including social interaction, cognitive function, acoustic startle, and amphetamine sensitivity, with some sex-dependent manifestations. In addition, 3q29 deletion mice showed reduced body weight throughout development consistent with the phenotype of 3q29 deletion syndrome patients. Of the genes within the interval, DLG1 has been hypothesized as a contributor to the neuropsychiatric phenotypes. However, we show that Dlg1+/- mice did not exhibit the behavioral deficits seen in mice harboring the full 3q29 deletion. These data demonstrate the following: the 3q29 deletion mice are a valuable experimental system that can be used to interrogate the biology of 3q29 deletion syndrome; behavioral manifestations of the 3q29 deletion may have sex-dependent effects; and mouse-specific behavior phenotypes associated with the 3q29 deletion are not solely due to haploinsufficiency of Dlg1.
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Affiliation(s)
- Timothy P. Rutkowski
- grid.189967.80000 0001 0941 6502Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322 USA
| | - Ryan H. Purcell
- grid.189967.80000 0001 0941 6502Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322 USA
| | - Rebecca M. Pollak
- grid.189967.80000 0001 0941 6502Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322 USA
| | - Stephanie M. Grewenow
- grid.189967.80000 0001 0941 6502Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322 USA
| | - Georgette M. Gafford
- grid.189967.80000 0001 0941 6502Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322 USA
| | - Tamika Malone
- grid.189967.80000 0001 0941 6502Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322 USA
| | - Uswa A. Khan
- grid.189967.80000 0001 0941 6502Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322 USA
| | - Jason P. Schroeder
- grid.189967.80000 0001 0941 6502Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322 USA
| | - Michael P. Epstein
- grid.189967.80000 0001 0941 6502Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322 USA
| | - Gary J. Bassell
- grid.189967.80000 0001 0941 6502Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322 USA
| | - Stephen T. Warren
- grid.189967.80000 0001 0941 6502Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322 USA
| | - David Weinshenker
- grid.189967.80000 0001 0941 6502Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322 USA
| | - Tamara Caspary
- grid.189967.80000 0001 0941 6502Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322 USA
| | - Jennifer Gladys Mulle
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, 30322, USA.
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Murphy MM, Burrell TL, Cubells JF, Epstein MT, Espana R, Gambello MJ, Goines K, Klaiman C, Koh S, Russo RS, Saulnier CA, Walker E, Mulle JG. Comprehensive phenotyping of neuropsychiatric traits in a multiplex 3q29 deletion family: a case report. BMC Psychiatry 2020; 20:184. [PMID: 32321479 PMCID: PMC7179007 DOI: 10.1186/s12888-020-02598-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 04/12/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND 3q29 deletion syndrome is associated with a range of medical, neurodevelopmental, and psychiatric phenotypes. The deletion is usually de novo but cases have been reported where the deletion is inherited from apparently unaffected parents. The presence of these unaffected or mildly affected individuals suggests there may be an ascertainment bias for severely affected cases of 3q29 deletion syndrome, thus the more deleterious consequence of the 3q29 deletion may be overestimated. However, a substantial fraction of 3q29 deletion syndrome morbidity is due to psychiatric illness. In many case reports, probands and transmitting parents are not systematically evaluated for psychiatric traits. Here we report results from a systematic phenotyping protocol for neurodevelopmental and neuropsychiatric traits applied to all 3q29 deletion carriers in a multiplex family. CASE PRESENTATION Through the 3q29 registry at Emory University, a multiplex family was identified where three offspring had a paternally inherited 3q29 deletion. We evaluated all 4 3q29 deletion family members using our previously described standardized, systematic phenotyping protocol. The transmitting parent reported no psychiatric history, however upon evaluation he was discovered to meet criteria for multiple psychiatric diagnoses including previously undiagnosed schizoaffective disorder. All four 3q29 deletion individuals in the pedigree had multiple psychiatric diagnoses that interfered with quality of life and prohibited successful academic and occupational functioning. Cognitive ability for all individuals was average or below average, but within the normal range. CONCLUSIONS This is the first case report of inherited 3q29 deletion syndrome where all affected individuals in the pedigree have been comprehensively and systematically evaluated for neurodevelopmental and psychiatric symptoms, using a standard battery of normed instruments administered by expert clinicians. Our investigation reveals that individuals with 3q29 deletion syndrome may have psychiatric morbidity that is debilitating, but only apparent through specialized evaluation by an expert. In the absence of appropriate evaluation, individuals with 3q29 deletion syndrome may suffer from psychiatric illness but lack avenues for access to care. The individuals evaluated here all have cognition in the normal range alongside multiple psychiatric diagnoses each, suggesting that cognitive ability alone is not a representative proxy for 3q29 deletion-associated disability. These results require replication in a larger cohort of individuals with 3q29 deletion syndrome.
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Affiliation(s)
- Melissa M Murphy
- Department of Human Genetics, Emory University School of Medicine, Whitehead 305M, 615 Michael Street, Atlanta, GA, 30322, USA
| | - T Lindsey Burrell
- Department of Pediatrics, Emory University School of Medicine, Atlanta, USA
- Marcus Autism Center, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, USA
| | - Joseph F Cubells
- Departments of Human Genetics and Psychiatry and Behavioral Science, Emory University School of Medicine, Atlanta, USA
| | - Michael T Epstein
- Department of Psychiatry and Behavioral Science, Emory University School of Medicine, Atlanta, USA
| | - Roberto Espana
- Department of Psychology, Emory University, Atlanta, USA
| | - Michael J Gambello
- Department of Human Genetics, Emory University School of Medicine, Whitehead 305M, 615 Michael Street, Atlanta, GA, 30322, USA
| | - Katrina Goines
- Department of Psychology, Emory University, Atlanta, USA
| | - Cheryl Klaiman
- Department of Pediatrics, Emory University School of Medicine, Atlanta, USA
- Marcus Autism Center, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, USA
| | - Sookyong Koh
- Department of Pediatrics, Emory University School of Medicine, Atlanta, USA
| | - Rossana Sanchez Russo
- Department of Human Genetics, Emory University School of Medicine, Whitehead 305M, 615 Michael Street, Atlanta, GA, 30322, USA
| | - Celine A Saulnier
- Department of Pediatrics, Emory University School of Medicine, Atlanta, USA
- Neurodevelopmental Assessment & Consulting Services, Decatur, USA
| | - Elaine Walker
- Department of Psychology, Emory University, Atlanta, USA
| | - Jennifer Gladys Mulle
- Department of Human Genetics, Emory University School of Medicine, Whitehead 305M, 615 Michael Street, Atlanta, GA, 30322, USA.
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, USA.
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8
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Murphy MM, Lindsey Burrell T, Cubells JF, España RA, Gambello MJ, Goines KCB, Klaiman C, Li L, Novacek DM, Papetti A, Sanchez Russo RL, Saulnier CA, Shultz S, Walker E, Mulle JG. Study protocol for The Emory 3q29 Project: evaluation of neurodevelopmental, psychiatric, and medical symptoms in 3q29 deletion syndrome. BMC Psychiatry 2018; 18:183. [PMID: 29884173 PMCID: PMC5994080 DOI: 10.1186/s12888-018-1760-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 05/22/2018] [Indexed: 03/06/2023] Open
Abstract
BACKGROUND 3q29 deletion syndrome is caused by a recurrent hemizygous 1.6 Mb deletion on the long arm of chromosome 3. The syndrome is rare (1 in 30,000 individuals) and is associated with mild to moderate intellectual disability, increased risk for autism and anxiety, and a 40-fold increased risk for schizophrenia, along with a host of physical manifestations. However, the disorder is poorly characterized, the range of manifestations is not well described, and the underlying molecular mechanism is not understood. We designed the Emory 3q29 Project to document the range of neurodevelopmental and psychiatric manifestations associated with 3q29 deletion syndrome. We will also create a biobank of samples from our 3q29 deletion carriers for mechanistic studies, which will be a publicly-available resource for qualified investigators. The ultimate goals of our study are three-fold: first, to improve management and treatment of 3q29 deletion syndrome. Second, to uncover the molecular mechanism of the disorder. Third, to enable cross-disorder comparison with other rare genetic syndromes associated with neuropsychiatric phenotypes. METHODS We will ascertain study subjects, age 6 and older, from our existing registry ( 3q29deletion.org ). Participants and their families will travel to Atlanta, GA for phenotypic assessments, with particular emphasis on evaluation of anxiety, cognitive ability, autism symptomatology, and risk for psychosis via prodromal symptoms and syndromes. Evaluations will be performed using standardized instruments. Structural, diffusion, and resting-state functional MRI data will be collected from eligible study participants. We will also collect blood from the 3q29 deletion carrier and participating family members, to be banked at the NIMH Repository and Genomics Resource (NRGR). DISCUSSION The study of 3q29 deletion has the potential to transform our understanding of complex disease. Study of individuals with the deletion may provide insights into long term care and management of the disorder. Our project describes the protocol for a prospective study of the behavioral and clinical phenotype associated with 3q29 deletion syndrome. The paradigm described here could easily be adapted to study additional CNV or single gene disorders with high risk for neuropsychiatric phenotypes, and/or transferred to other study sites, providing a means for data harmonization and cross-disorder analysis.
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Affiliation(s)
- Melissa M. Murphy
- 0000 0001 0941 6502grid.189967.8Department of Human Genetics, Emory University School of Medicine, Whitehead Research Building, 615 Michael Street, Suite 300, Atlanta, GA 30322 USA
| | - T. Lindsey Burrell
- 0000 0001 0941 6502grid.189967.8Department of Pediatrics, Emory University School of Medicine, 1920 Briarcliff Road NE, Atlanta, GA 30322 USA ,0000 0004 0371 6071grid.428158.2Marcus Autism Center, 1920 Briarcliff Road NE, Atlanta, GA 30322 USA
| | - Joseph F. Cubells
- 0000 0001 0941 6502grid.189967.8Department of Human Genetics, Emory University School of Medicine, Whitehead Research Building, 615 Michael Street, Suite 300, Atlanta, GA 30322 USA ,Emory Autism Center, 1551 Shoup Court, Atlanta, GA 30322 USA ,0000 0001 0941 6502grid.189967.8Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, 12 Executive Park Drive, 2nd floor, Atlanta, GA 30329 USA
| | - Roberto Antonio España
- 0000 0001 0941 6502grid.189967.8Department of Psychology, Emory University, 36 Eagle Row, Atlanta, GA 30322 USA
| | - Michael J. Gambello
- 0000 0001 0941 6502grid.189967.8Department of Human Genetics, Emory University School of Medicine, Whitehead Research Building, 615 Michael Street, Suite 300, Atlanta, GA 30322 USA
| | - Katrina C. B. Goines
- 0000 0001 0941 6502grid.189967.8Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, 12 Executive Park Drive, 2nd floor, Atlanta, GA 30329 USA ,0000 0001 0941 6502grid.189967.8Department of Psychology, Emory University, 36 Eagle Row, Atlanta, GA 30322 USA
| | - Cheryl Klaiman
- 0000 0001 0941 6502grid.189967.8Department of Pediatrics, Emory University School of Medicine, 1920 Briarcliff Road NE, Atlanta, GA 30322 USA ,0000 0004 0371 6071grid.428158.2Marcus Autism Center, 1920 Briarcliff Road NE, Atlanta, GA 30322 USA
| | - Longchuan Li
- 0000 0001 0941 6502grid.189967.8Department of Pediatrics, Emory University School of Medicine, 1920 Briarcliff Road NE, Atlanta, GA 30322 USA ,0000 0004 0371 6071grid.428158.2Marcus Autism Center, 1920 Briarcliff Road NE, Atlanta, GA 30322 USA
| | - Derek M. Novacek
- 0000 0001 0941 6502grid.189967.8Department of Psychology, Emory University, 36 Eagle Row, Atlanta, GA 30322 USA
| | - Ava Papetti
- 0000 0001 0941 6502grid.189967.8Department of Human Genetics, Emory University School of Medicine, Whitehead Research Building, 615 Michael Street, Suite 300, Atlanta, GA 30322 USA
| | - Rossana Lucia Sanchez Russo
- 0000 0001 0941 6502grid.189967.8Department of Human Genetics, Emory University School of Medicine, Whitehead Research Building, 615 Michael Street, Suite 300, Atlanta, GA 30322 USA
| | - Celine A. Saulnier
- 0000 0001 0941 6502grid.189967.8Department of Pediatrics, Emory University School of Medicine, 1920 Briarcliff Road NE, Atlanta, GA 30322 USA
| | - Sarah Shultz
- 0000 0001 0941 6502grid.189967.8Department of Pediatrics, Emory University School of Medicine, 1920 Briarcliff Road NE, Atlanta, GA 30322 USA ,0000 0004 0371 6071grid.428158.2Marcus Autism Center, 1920 Briarcliff Road NE, Atlanta, GA 30322 USA
| | - Elaine Walker
- 0000 0001 0941 6502grid.189967.8Department of Psychology, Emory University, 36 Eagle Row, Atlanta, GA 30322 USA
| | - Jennifer Gladys Mulle
- Department of Human Genetics, Emory University School of Medicine, Whitehead Research Building, 615 Michael Street, Suite 300, Atlanta, GA, 30322, USA. .,Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, 30322, USA.
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9
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Affiliation(s)
- J G Mulle
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA,Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA,E-mail:
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10
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Moreno-De-Luca D, Sanders SJ, Willsey AJ, Mulle JG, Lowe JK, Geschwind DH, State MW, Martin CL, Ledbetter DH. Using large clinical data sets to infer pathogenicity for rare copy number variants in autism cohorts. Mol Psychiatry 2013; 18:1090-5. [PMID: 23044707 PMCID: PMC3720840 DOI: 10.1038/mp.2012.138] [Citation(s) in RCA: 124] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Revised: 07/24/2012] [Accepted: 08/20/2012] [Indexed: 11/16/2022]
Abstract
Copy number variants (CNVs) have a major role in the etiology of autism spectrum disorders (ASD), and several of these have reached statistical significance in case-control analyses. Nevertheless, current ASD cohorts are not large enough to detect very rare CNVs that may be causative or contributory (that is, risk alleles). Here, we use a tiered approach, in which clinically significant CNVs are first identified in large clinical cohorts of neurodevelopmental disorders (including but not specific to ASD), after which these CNVs are then systematically identified within well-characterized ASD cohorts. We focused our initial analysis on 48 recurrent CNVs (segmental duplication-mediated 'hotspots') from 24 loci in 31 516 published clinical cases with neurodevelopmental disorders and 13 696 published controls, which yielded a total of 19 deletion CNVs and 11 duplication CNVs that reached statistical significance. We then investigated the overlap of these 30 CNVs in a combined sample of 3955 well-characterized ASD cases from three published studies. We identified 73 deleterious recurrent CNVs, including 36 deletions from 11 loci and 37 duplications from seven loci, for a frequency of 1 in 54; had we considered the ASD cohorts alone, only 58 CNVs from eight loci (24 deletions from three loci and 34 duplications from five loci) would have reached statistical significance. In conclusion, until there are sufficiently large ASD research cohorts with enough power to detect very rare causative or contributory CNVs, data from larger clinical cohorts can be used to infer the likely clinical significance of CNVs in ASD.
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Affiliation(s)
- D Moreno-De-Luca
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA,Programs in Neurogenetics and Human Genetics and Genomics, Child Study Center and Departments of Psychiatry and Genetics, Yale University School of Medicine, New Haven, CT, USA,Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Suite 315, Atlanta, GA 30322, USAE-mail:
| | - S J Sanders
- Programs in Neurogenetics and Human Genetics and Genomics, Child Study Center and Departments of Psychiatry and Genetics, Yale University School of Medicine, New Haven, CT, USA
| | - A J Willsey
- Programs in Neurogenetics and Human Genetics and Genomics, Child Study Center and Departments of Psychiatry and Genetics, Yale University School of Medicine, New Haven, CT, USA
| | - J G Mulle
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - J K Lowe
- Neurogenetics Program, University of California, Los Angeles, Los Angeles, CA, USA
| | - D H Geschwind
- Neurogenetics Program, University of California, Los Angeles, Los Angeles, CA, USA
| | - M W State
- Programs in Neurogenetics and Human Genetics and Genomics, Child Study Center and Departments of Psychiatry and Genetics, Yale University School of Medicine, New Haven, CT, USA
| | - C L Martin
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
| | - D H Ledbetter
- Genomic Medicine Institute, Geisinger Health System, Danville, PA, USA,Genomic Medicine Institute, Geisinger Health System, Danville, PA, USA. E-mail:
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11
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Abstract
Psychosocial factors are associated with cardiovascular disease, but little is known about the role of genetics in this relationship. Focusing on the well-studied phenotype of depression, current data show that there are shared genetic factors that may give rise to both depression and CVD, and these genetic risks appear to be modified by gender. This pleiotropic effect suggests that a single pathway, when perturbed, gives rise to the dual phenotypes of CVD and depression. The data also suggest that women contribute disproportionately to the depression-CVD comorbidity, and this unbalanced contribution is attributable, in part, to genetic factors. While the underlying biology behind this relationship is unclear, recent data support contributions from inflammatory or serotonergic pathways toward the comorbidity between CVD and depression. Even without knowledge of a specific mechanism, epidemiological observations offer new directions to explain the relationship between depression and CVD that have both research and clinical applications.
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Affiliation(s)
- Jennifer Gladys Mulle
- Department of Epidemiology, Rollins School of Public Health, Emory University, GA 30322, USA.
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12
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Mulle JG. Schizophrenia genetics: progress, at last. Curr Opin Genet Dev 2012; 22:238-44. [DOI: 10.1016/j.gde.2012.02.011] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2011] [Revised: 02/14/2012] [Accepted: 02/15/2012] [Indexed: 12/15/2022]
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Mulle JG, Dodd AF, McGrath JA, Wolyniec PS, Mitchell AA, Shetty AC, Sobreira NL, Valle D, Rudd MK, Satten G, Cutler DJ, Pulver AE, Warren ST. Microdeletions of 3q29 confer high risk for schizophrenia. Am J Hum Genet 2010; 87:229-36. [PMID: 20691406 DOI: 10.1016/j.ajhg.2010.07.013] [Citation(s) in RCA: 173] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2010] [Revised: 07/19/2010] [Accepted: 07/22/2010] [Indexed: 01/02/2023] Open
Abstract
Schizophrenia (SZ) is a severe psychiatric illness that affects approximately 1% of the population and has a strong genetic underpinning. Recently, genome-wide analysis of copy-number variation (CNV) has implicated rare and de novo events as important in SZ. Here, we report a genome-wide analysis of 245 SZ cases and 490 controls, all of Ashkenazi Jewish descent. Because many studies have found an excess burden of large, rare deletions in cases, we limited our analysis to deletions over 500 kb in size. We observed seven large, rare deletions in cases, with 57% of these being de novo. We focused on one 836 kb de novo deletion at chromosome 3q29 that falls within a 1.3-1.6 Mb deletion previously identified in children with intellectual disability (ID) and autism, because increasing evidence suggests an overlap of specific rare copy-number variants (CNVs) between autism and SZ. By combining our data with prior CNV studies of SZ and analysis of the data of the Genetic Association Information Network (GAIN), we identified six 3q29 deletions among 7545 schizophrenic subjects and one among 39,748 controls, resulting in a statistically significant association with SZ (p = 0.02) and an odds ratio estimate of 17 (95% confidence interval: 1.36-1198.4). Moreover, this 3q29 deletion region contains two linkage peaks from prior SZ family studies, and the minimal deletion interval implicates 20 annotated genes, including PAK2 and DLG1, both paralogous to X-linked ID genes and now strong candidates for SZ susceptibility.
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Abstract
It has recently been demonstrated that a large amount of structural variation exists in the human genome. Since 2004, when two landmark studies reported polymorphic levels of copy number variation in phenotypically normal individuals, our understanding of genome-wide levels of copy number variation has grown. This has inspired hypotheses about this class of variation's contribution to complex genetic phenotypes, including the specific hypothesis that structural variation is associated with psychiatric illness. The technology to accurately and efficiently detect polymorphic structural variants is still largely under development, but some examples of genomic imbalance contributing to schizophrenia and bipolar disorder already have been identified. Although much optimism surrounds this burgeoning field, the technical challenges in reliably identifying structural variation mean recent literature should be approached with caution.
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Affiliation(s)
- Jennifer Gladys Mulle
- Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Atlanta, GA 30317, USA.
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Mulle JG, Fallin MD, Lasseter VK, McGrath JA, Wolyniec PS, Pulver AE. Dense SNP association study for bipolar I disorder on chromosome 18p11 suggests two loci with excess paternal transmission. Mol Psychiatry 2007; 12:367-75. [PMID: 17389904 DOI: 10.1038/sj.mp.4001916] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Parent-of-origin effects have been implicated as mediators of genetic susceptibility for a number of complex disease phenotypes, including bipolar disorder. Specifically, evidence for linkage on chromosome 18 is modified when allelic parent-of-origin is accommodated in the analysis. Our goal was to characterize the susceptibility locus for bipolar I disorder on chromosome 18p11 and investigate this parent-of-origin hypothesis in an association context. This was achieved by genotyping single nucleotide polymorphisms (SNPs) at a high density (1 SNP/5 kb) along 13.6 megabases of the linkage region. To increase our ability to detect a susceptibility locus, we restricted the phenotype definition to include only bipolar I probands. We also restricted our study population to Ashkenazi Jewish individuals; this population has characteristics of a genetic isolate and may therefore facilitate detection of variants for complex disease. Three hundred and forty-four pedigrees (363 parent/child trios) where probands were affected with bipolar 1 disorder were genotyped. Transmission disequilibrium test analysis revealed no statistically significant association to SNPs or haplotypes within this region in this sample. However, when parent-of-origin of transmitted SNPs was taken into account, suggestive association was revealed for two separate loci.
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Affiliation(s)
- J G Mulle
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins School of Medicine, Baltimore, MD 21231, USA
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Mulle JG, McDonough JA, Chowdari KV, Nimgaonkar V, Chakravarti A. Evidence for linkage to chromosome 13q32 in an independent sample of schizophrenia families. Mol Psychiatry 2005; 10:429-31. [PMID: 15738936 DOI: 10.1038/sj.mp.4001639] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Mulle JG, Chowdari KV, Nimgaonkar V, Chakravarti A. No evidence for association to the G72/G30 locus in an independent sample of schizophrenia families. Mol Psychiatry 2005; 10:431-3. [PMID: 15753958 DOI: 10.1038/sj.mp.4001619] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Peterson BZ, Lee JS, Mulle JG, Wang Y, de Leon M, Yue DT. Critical determinants of Ca(2+)-dependent inactivation within an EF-hand motif of L-type Ca(2+) channels. Biophys J 2000; 78:1906-20. [PMID: 10733970 PMCID: PMC1300784 DOI: 10.1016/s0006-3495(00)76739-7] [Citation(s) in RCA: 163] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
L-type (alpha(1C)) calcium channels inactivate rapidly in response to localized elevation of intracellular Ca(2+), providing negative Ca(2+) feedback in a diverse array of biological contexts. The dominant Ca(2+) sensor for such Ca(2+)-dependent inactivation has recently been identified as calmodulin, which appears to be constitutively tethered to the channel complex. This Ca(2+) sensor induces channel inactivation by Ca(2+)-dependent CaM binding to an IQ-like motif situated on the carboxyl tail of alpha(1C). Apart from the IQ region, another crucial site for Ca(2+) inactivation appears to be a consensus Ca(2+)-binding, EF-hand motif, located approximately 100 amino acids upstream on the carboxyl terminus. However, the importance of this EF-hand motif for channel inactivation has become controversial since the original report from our lab implicating a critical role for this domain. Here, we demonstrate not only that the consensus EF hand is essential for Ca(2+) inactivation, but that a four-amino acid cluster (VVTL) within the F helix of the EF-hand motif is itself essential for Ca(2+) inactivation. Mutating these amino acids to their counterparts in non-inactivating alpha(1E) calcium channels (MYEM) almost completely ablates Ca(2+) inactivation. In fact, only a single amino acid change of the second valine within this cluster to tyrosine (V1548Y) supports much of the functional knockout. However, mutations of presumed Ca(2+)-coordinating residues in the consensus EF hand reduce Ca(2+) inactivation by only approximately 2-fold, fitting poorly with the EF hand serving as a contributory inactivation Ca(2+) sensor, in which Ca(2+) binds according to a classic mechanism. We therefore suggest that while CaM serves as Ca(2+) sensor for inactivation, the EF-hand motif of alpha(1C) may support the transduction of Ca(2+)-CaM binding into channel inactivation. The proposed transduction role for the consensus EF hand is compatible with the detailed Ca(2+)-inactivation properties of wild-type and mutant V1548Y channels, as gauged by a novel inactivation model incorporating multivalent Ca(2+) binding of CaM.
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Affiliation(s)
- B Z Peterson
- Program in Molecular and Cellular Systems Physiology, Departments of Biomedical Engineering and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland, 21205 USA
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Cai D, Mulle JG, Yue DT. Inhibition of recombinant Ca2+ channels by benzothiazepines and phenylalkylamines: class-specific pharmacology and underlying molecular determinants. Mol Pharmacol 1997; 51:872-81. [PMID: 9145926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
To understand the molecular basis of state-dependent pharmacological blockade of voltage-gated Ca2+ channels, we systematically characterized phenylalkylamine and benzothiazepine inhibition of three molecular classes of Ca2+ channels (alpha1C, alpha1A, and alpha1E) expressed from cDNA clones transfected into HEK 293 cells. State-dependent blockade figures importantly in the therapeutically desirable property of use-dependent drug action. Verapamil (a phenylalkylamine) and diltiazem (a benzothiazepine) were imperfectly selective, so differences in the state dependence of inhibition could be compared among the various channels. We found only quantitative differences in pharmacological profile of verapamil: half-maximal inhibitory concentrations spanned a 2-fold range (70 microM for alpha1A, 100 microM for alpha1E, and 110 microM for alpha1C), and inhibition was state dependent in all channels. In contrast, diltiazem produced only state-dependent block of alpha1C channels; alpha1A and alpha1E channels demonstrated state-independent block despite similar half-maximal inhibitory concentrations (60 microM for alpha1C, 220 microM for alpha1E, and 270 microM for alpha1A). To explore the molecular basis for the sharp distinction in state-dependent inhibition by diltiazem, we constructed chimeric channels from alpha1C and alpha1A and localized the structural determinants for state dependence to repeats III and IV of alpha1C, which have been found to contain the structures required for benzothiazepine binding. We then constructed a mutant alpha1C construct by changing three amino acids in IVS6 (Y14901, A1494S, 11497M) that have been implicated as key coordinating sites for avid benzothiazepine binding. Although these mutations increased the half-maximal inhibitory concentration of diltiazem inhibition by approximately 10-fold, the state-dependent nature of inhibition was spared. This result points to the existence of physically distinct elements controlling drug binding and access to the binding site, thereby favoring a "guarded-receptor" rather than a "modulated-receptor" mechanism of drug inhibition.
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Affiliation(s)
- D Cai
- Department of Biomedical Engineering, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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20
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Brody DL, Patil PG, Mulle JG, Snutch TP, Yue DT. Bursts of action potential waveforms relieve G-protein inhibition of recombinant P/Q-type Ca2+ channels in HEK 293 cells. J Physiol 1997; 499 ( Pt 3):637-44. [PMID: 9130160 PMCID: PMC1159282 DOI: 10.1113/jphysiol.1997.sp021956] [Citation(s) in RCA: 96] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
1. A variety of neurotransmitters act through G-protein-coupled receptors to decrease synaptic transmission, largely by inhibiting the voltage-gated calcium channels that trigger neurotransmitter release. However, these presynaptic calcium channels are typically inaccessible to electrophysiological characterization. We have reconstituted a part of this inhibition using recombinant P/Q-type calcium channels and M2 acetylcholine receptors in HEK 293 cells. 2. One of the most interesting features of G-protein inhibition of calcium channels is that strong step depolarization transiently relieves the inhibition. We have found that short bursts of action potential voltage waveforms can also relieve the inhibition, increasing calcium current through G-protein-inhibited channels but not through uninhibited channels. 3. The extent of this relief increased linearly with the duration of the action potential waveforms. 4. This result provides the strongest evidence to date favouring the possibility that relief of G-protein inhibition can occur during high frequency trains of action potentials. This effect may constitute a novel form of short-term synaptic plasticity that is sensitive to action potential timing and duration.
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Affiliation(s)
- D L Brody
- Johns Hopkins University, Department of Biomedical Engineering, Baltimore, MD 21205, USA
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