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Entezam A, Usdin K. ATM and ATR protect the genome against two different types of tandem repeat instability in Fragile X premutation mice. Nucleic Acids Res 2009; 37:6371-7. [PMID: 19710035 PMCID: PMC2770655 DOI: 10.1093/nar/gkp666] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Expansion of a tandem repeat tract is responsible for the Repeat Expansion diseases, a group of more than 20 human genetic disorders that includes those like Fragile X (FX) syndrome that result from repeat expansion in the FMR1 gene. We have previously shown that the ATM and Rad3-related (ATR) checkpoint kinase protects the genome against one type of repeat expansion in a FX premutation mouse model. By crossing the FX premutation mice to Ataxia Telangiectasia-Mutated (Atm) mutant mice, we show here that ATM also prevents repeat expansion. However, our data suggest that the ATM-sensitive mechanism is different from the ATR-sensitive one. Specifically, the effect of the ATM deficiency is more marked when the premutation allele is paternally transmitted and expansions occur more frequently in male offspring regardless of the Atm genotype of the offspring. The gender effect is most consistent with a repair event occurring in the early embryo that is more efficient in females, perhaps as a result of the action of an X-linked DNA repair gene. Our data thus support the hypothesis that two different mechanisms of FX repeat expansion exist, an ATR-sensitive mechanism seen on maternal transmission and an ATM-sensitive mechanism that shows a male expansion bias.
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Affiliation(s)
- Ali Entezam
- Laboratory of Molecular and Cellular Biology, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0830, USA
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102
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Bourgeois J, Coffey S, Rivera SM, Hessl D, Gane LW, Tassone F, Greco C, Finucane B, Nelson L, Berry-Kravis E, Grigsby J, Hagerman PJ, Hagerman RJ. A review of fragile X premutation disorders: expanding the psychiatric perspective. J Clin Psychiatry 2009; 70:852-62. [PMID: 19422761 PMCID: PMC2705685 DOI: 10.4088/jcp.08m04476] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2008] [Accepted: 11/11/2008] [Indexed: 01/28/2023]
Abstract
CONTEXT Fragile X premutation conditions are associated with a significant degree of psychopathology and thus are of interest to the psychiatrist. Remarkable advances at the molecular level have enhanced our understanding of fragile X premutation disorders. OBJECTIVE The authors review the genetic, molecular, neuroimaging, and clinical (systemic, neurologic, and psychiatric) manifestations of the premutation carrier state (55-200 CGG repeats) of the fragile X mental retardation 1 (FMR1) gene. DATA SOURCES The search for the psychiatric clinical manifestations of fragile X-associated conditions was accomplished by PubMed for clinical papers published between 1970 and 2008 with the following search terms: Fragile X syndrome, depression, psychosis, anxiety, and dementia. STUDY SELECTION Articles addressing psychiatric symptoms in premutation carriers based on review of the abstracts were reviewed. As the majority of the literature on this topic is based on case reports and small case series, these were included in the database. RESULTS Reported clinical manifestations of psychiatric illness in premutation carriers include an apparently significant rate of cognitive, mood, anxiety, and other psychiatric disorders. Fragile X premutation-associated conditions are part of the clinical differential diagnosis of several psychiatric syndromes, particularly in pedigrees with known fragile X syndrome cases. CONCLUSIONS Fragile X-associated psychiatric manifestations serve as a useful model for a molecular genesis of neuropsychiatric illness. Because of the multigenerational expression of fragile X-associated neuropsychiatric illness, there is a prominent role for genetic testing and genetic counseling of patients and their relatives. Genetic testing is confirmatory of the FMR1 premutation and is an essential component of the clinical evaluation. Psychopharmacologic and psychotherapeutic treatment of fragile X-associated psychiatric illnesses may improve patient function and assist in adaptation to the burden of a genetic neuropsychiatric illness.
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Affiliation(s)
- James Bourgeois
- Department of Psychiatry and Behavioral Sciences, University of California, Davis Medical Center, Sacramento, CA
| | - Sarah Coffey
- M.I.N.D. Institute, University of California, Davis Medical Center, Sacramento, CA., Department of Pediatrics, University of California, Davis Medical Center, Sacramento, CA
| | - Susan M. Rivera
- M.I.N.D. Institute, University of California, Davis Medical Center, Sacramento, CA., Department of Psychology, University of California, Davis
| | - David Hessl
- M.I.N.D. Institute, University of California, Davis Medical Center, Sacramento, CA., Department of Psychiatry and Behavioral Sciences, University of California, Davis, Sacramento, CA
| | - Louise W. Gane
- M.I.N.D. Institute, University of California, Davis Medical Center, Sacramento, CA
| | - Flora Tassone
- M.I.N.D. Institute, University of California, Davis Medical Center, Sacramento, CA., Department of Biochemistry and Molecular Medicine, University of California, Davis, School of Medicine, Sacramento, CA
| | - Claudia Greco
- Department of Pathology, University of California, Davis Medical Center, School of Medicine, Sacramento, CA
| | - Brenda Finucane
- Genetic Services, Elwyn, Inc., 111 Elwyn Road, Elwyn, Pennsylvania
| | - Lawrence Nelson
- Integrative Reproductive Medicine Unit, Intramural Research Program on Reproductive and Adult Endocrinology, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD
| | - Elizabeth Berry-Kravis
- Departments of Pediatrics, Neurological Sciences, and Biochemistry, RUSH University Medical Center, Chicago, IL
| | - Jim Grigsby
- Department of Medicine, University of Colorado at Denver and Health Sciences Center, Denver, CO
| | - Paul J. Hagerman
- Department of Biochemistry and Molecular Medicine, University of California, Davis, School of Medicine, Sacramento, CA
| | - Randi J. Hagerman
- M.I.N.D. Institute, University of California, Davis Medical Center, Sacramento, CA., Department of Pediatrics, University of California, Davis Medical Center, Sacramento, CA
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103
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Sallansonnet-Froment M, De Greslan T, Roux X, Bounolleau P, Ouologuem M, Taillia H, Ricard D, Renard JL. [Tremor/ataxia syndrome related to Fragile X premutation]. Presse Med 2009; 39:187-95. [PMID: 19419833 DOI: 10.1016/j.lpm.2008.12.035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2008] [Revised: 12/20/2008] [Accepted: 12/31/2008] [Indexed: 11/20/2022] Open
Abstract
The FXTAS syndrome (Fragile X-associated tremor/ataxia syndrome) is a specific neurodegenerative syndrome affecting subjects carrying a premutation of the FMR1 (fragile X mental retardation 1) gene. It affects mainly men with the premutation and aged more than 50 years. This syndrome is separate and distinct from the fragile X syndrome. The FXTAS syndrome remains underestimated today. It should be considered in patients older than 50 years with tremors and cerebellar ataxia, especially when Parkinson disease or cognitive disorders are present or when there is a family history of infertility, early menopause, or mental retardation. In these patients, hyperintense signals of mid-cerebellar peduncle images on T2 and FLAIR MRI justify genetic testing for the FMR1 premutation.
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Affiliation(s)
- Magali Sallansonnet-Froment
- Hôpital d'instruction des armées du Val-de-Grâce, Service de neurologie, F-75230 Paris Cedex 05, B.P.1-00446 Armées, France.
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104
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Oostra BA, Willemsen R. FMR1: a gene with three faces. Biochim Biophys Acta Gen Subj 2009; 1790:467-77. [PMID: 19233246 DOI: 10.1016/j.bbagen.2009.02.007] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2008] [Revised: 02/09/2009] [Accepted: 02/10/2009] [Indexed: 11/19/2022]
Abstract
The FMR1 gene is involved in three different syndromes, the fragile X syndrome (FXS), premature ovarian insufficiency (POI) and the fragile X-associated tremor/ataxia syndrome (FXTAS) at older age. Fragile X syndrome is caused by an expansion of a CGG repeat above 200 units in the FMR1 gene resulting in the absence of the FMR1 mRNA and protein. The FMR1 protein is proposed to act as a regulator of mRNA transport and of translation of target mRNAs at the synapse. FXS is seen as a loss of function disorder. POI and FXTAS are found in individuals with an expanded repeat between 50 and 200 CGGs and are associated with increased FMR1 mRNA levels. The presence of elevated FMR1 mRNA in FXTAS suggests that FXTAS may represent a toxic RNA gain-of-function effect. The molecular basis of POI is yet unknown. The role of the FMR1 gene in these disorders is discussed.
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Affiliation(s)
- Ben A Oostra
- Department of Clinical Genetics, Erasmus MC, P.O. Box 2040, 3000 CA Rotterdam, The Netherlands.
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105
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Brouwer JR, Huizer K, Severijnen LA, Hukema RK, Berman RF, Oostra BA, Willemsen R. CGG-repeat length and neuropathological and molecular correlates in a mouse model for fragile X-associated tremor/ataxia syndrome. J Neurochem 2008; 107:1671-82. [PMID: 19014369 DOI: 10.1111/j.1471-4159.2008.05747.x] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The 5'untranslated region (UTR) of the FMR1 gene contains a CGG-repeat, which may become unstable upon transmission to the next generation. When repeat length exceeds 200, the FMR1 gene generally undergoes methylation-mediated transcriptional silencing. The subsequent absence of the gene product Fragile X Mental Retardation Protein (FMRP)causes the mental retardation seen in fragile X patients. A CGG-repeat length between 55 and 200 trinucleotides has been termed the premutation (PM). Predominantly elderly male PM carriers are at risk of developing a progressive neurodegenerative disorder: fragile X-associated tremor/ataxia syndrome (FXTAS). All PM carriers have elevated FMR1 mRNA levels, in spite of slightly decreased FMRP levels. The presence of intranuclear ubiquitin-positive inclusions in many brain regions is a neuropathological hallmark of FXTAS. Studies in humans attempting to correlate neuropathological outcomes with molecular measures are difficult because of the limited availability of tissue. Therefore, we have used the expanded CGG-repeat knock-in mouse model of FXTAS to examine the relationship between the molecular and neuropathological parameters in brain. We present Fmr1 mRNA and Fmrp levels and the presence of intranuclear inclusions at different repeat lengths. Contrary to existing hypotheses, our results suggest that inclusion formation may not depend on the elevation per se of Fmr1 transcript levels in aged CGG mice.
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Affiliation(s)
- Judith R Brouwer
- Department of Clinical Genetics, Erasmus MC Rotterdam, GE Rotterdam, The Netherlands
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106
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Chaussenot A, Borg M, Bayreuther C, Lebrun C. Ataxie cérébelleuse tardive due à la prémutation de l’X fragile. Rev Neurol (Paris) 2008; 164:957-63. [DOI: 10.1016/j.neurol.2008.03.022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2007] [Revised: 02/05/2008] [Accepted: 03/11/2008] [Indexed: 10/22/2022]
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107
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Hagerman RJ, Hall DA, Coffey S, Leehey M, Bourgeois J, Gould J, Zhang L, Seritan A, Berry-Kravis E, Olichney J, Miller JW, Fong AL, Carpenter R, Bodine C, Gane LW, Rainin E, Hagerman H, Hagerman PJ. Treatment of fragile X-associated tremor ataxia syndrome (FXTAS) and related neurological problems. Clin Interv Aging 2008; 3:251-62. [PMID: 18686748 PMCID: PMC2546470 DOI: 10.2147/cia.s1794] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Fragile X-associated tremor/ataxia syndrome (FXTAS) is a progressive neurological disorder that affects older adult carriers, predominantly males, of premutation alleles (55 to 200 CGG repeats) of the fragile X (FMR1) gene. Principal features of FXTAS are intention tremor, ataxia, parkinsonism, cognitive decline, and peripheral neuropathy; ancillary features include, autonomic dysfunction, and psychiatric symptoms of anxiety, depression, and disinhibition. Although controlled trials have not been carried out in individuals with FXTAS, there is a significant amount of anecdotal information regarding various treatment modalities. Moreover, there exists a great deal of evidence regarding the efficacy of various medications for treatment of other disorders (eg, Alzheimer disease) that have substantial phenotypic overlap with FXTAS. The current review summarizes what is currently known regarding the symptomatic treatment, or potential for treatment, of FXTAS.
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Affiliation(s)
- Randi J Hagerman
- MIND Institute, University of California, Davis, School of Medicine, Sacramento, CA 95817, USA.
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108
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Seritan AL, Nguyen DV, Tomaszewski Farias S, Hinton L, Grigsby J, Bourgeois JA, Hagerman R. Dementia in fragile X-associated tremor/ataxia syndrome (FXTAS): comparison with Alzheimer's disease. Am J Med Genet B Neuropsychiatr Genet 2008; 147B:1138-44. [PMID: 18384046 PMCID: PMC2898561 DOI: 10.1002/ajmg.b.30732] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Neurocognitive deficits in fragile X-associated tremor/ataxia syndrome (FXTAS) involve attentional control, working memory, executive functioning, and declarative and procedural learning. To date, no studies comparing FXTAS with other dementias have been done. We characterize the dementia in FXTAS, comparing it with Alzheimer's disease. Retrospective chart review of 68 adults (50 men, 18 women) with FXTAS. 20 men with FXTAS dementia were matched by age, gender, and education to patients with mild Alzheimer's dementia (AD). Neuropsychological measures were compared between the two groups: Boston Naming Test (BNT), phonemic fluency (Controlled Oral Word Association Test), digit span forward (DSF) and backward (DSB). Comparisons were based on analysis of covariance and t-tests to assess significant differences between groups. 50% of men with FXTAS and no women were cognitively impaired. On mean scores of verbal fluency (22.83 in FXTAS vs. 28.83 in AD, P = 0.112), working memory (DSB, 4.80 in AD vs. 5.41 in FXTAS, P = 0.359), and language (BNT, 48.54 in AD vs. 54.20 in FXTAS, P = 0.089), there were no significant differences. Digit span forward, measuring attention, was significantly higher in subjects with FXTAS dementia (8.59, vs. 7.10 in AD, P = 0.010). Individuals with FXTAS have significant cognitive deficits, on the order of those in AD although the cognitive profiles in these dementias are not similar. Further research is needed to outline the neuropsychiatric profile in FXTAS and the correlation of genetic markers with the progression and severity of cognitive loss.
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Affiliation(s)
- Andreea L. Seritan
- Department of Psychiatry and Behavioral Sciences, University of California at Davis, Sacramento, CA
| | - Danh V. Nguyen
- Department of Public Health Sciences, University of California at Davis, School of Medicine, Davis, CA
| | | | - Ladson Hinton
- Department of Psychiatry and Behavioral Sciences, University of California at Davis, Sacramento, CA
| | - Jim Grigsby
- Department of Medicine, University of Colorado Health Sciences Center, Aurora, CO
| | - James A. Bourgeois
- Department of Psychiatry and Behavioral Sciences, University of California at Davis, Sacramento, CA
| | - Randi Hagerman
- M.I.N.D. Institute, University of California at Davis Medical Center, Sacramento, CA.,Department of Pediatrics, University of California at Davis Medical Center, Sacramento, CA
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109
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Bailey DB, Raspa M, Olmsted M, Holiday DB. Co-occurring conditions associated with FMR1 gene variations: findings from a national parent survey. Am J Med Genet A 2008; 146A:2060-9. [PMID: 18570292 DOI: 10.1002/ajmg.a.32439] [Citation(s) in RCA: 332] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Parents enrolling in a national survey of families of children with fragile X (FX) reported whether each of their children had been diagnosed or treated for developmental delay or eight conditions frequently associated with FX: attention problems, hyperactivity, aggressiveness, self-injury, autism, seizures, anxiety, or depression. This article reports results for 976 full mutation males, 259 full mutation females, 57 premutation males, and 199 premutation females. Co-occurring conditions were frequently reported for all FMR1 gene variations. The number of co-occurring conditions experienced was strongly associated with parent reports of their child's ability to learn, adaptability, and quality of life. Most individuals with the full mutation experienced multiple co-occurring conditions, with a modal number of 4 for males and 2 for females. Most (>80%) full mutation males and females had been diagnosed or treated for attention problems. Premutation males, when compared with a matched group of non-FX males, were more likely to have been diagnosed or treated for developmental delay, attention problems, aggression, seizures, autism, and anxiety. Premutation females were more likely to have been diagnosed or treated for attention problems, anxiety, depression, and developmental delay. Clusters of conditions were identified, seeming to occur in an additive fashion. Self-injury, autism, and seizures rarely occurred in isolation, but were more likely in individuals who also had problems with attention, anxiety, and hyperactivity. The findings provide a reference point for future studies on the prevalence and nature of co-occurring conditions in FX; suggest the possibility that certain conditions cluster together; provide evidence that male and female carriers experience elevated rates of co-occurring conditions compared with matched groups of non-carrier children; and emphasize the importance of including an assessment of co-occurring conditions in any clinical evaluation of individuals with abnormal variation in the FMR1 gene.
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Affiliation(s)
- Donald B Bailey
- RTI International, Research Triangle Park, North Carolina 27709-2194, USA.
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110
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Hall DA, Howard K, Hagerman R, Leehey MA. Parkinsonism in FMR1 premutation carriers may be indistinguishable from Parkinson disease. Parkinsonism Relat Disord 2008; 15:156-9. [PMID: 18565783 DOI: 10.1016/j.parkreldis.2008.04.037] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2008] [Revised: 04/23/2008] [Accepted: 04/25/2008] [Indexed: 12/14/2022]
Abstract
Premutation carriers of repeat expansions in the fragile X mental retardation (FMR1) gene develop kinetic tremor and ataxia or the 'fragile X associated tremor/ataxia syndrome' (FXTAS). Affected FMR1 premutation carriers also have parkinsonism, but have not been reported to meet criteria for Parkinson disease. This case series illustrates that some patients who are FMR1 premutation carriers may appear by history and examination to have idiopathic Parkinson disease. Based on previous studies, it is likely that the genetic mutation and parkinsonism are associated. Although screening all PD patients is likely to be low yield, genetic testing of FMR1 in individuals with PD and a family history of fragile X syndrome, autism or developmental delay, or other related FMR1 phenotypes is warranted.
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Affiliation(s)
- Deborah A Hall
- Department of Neurology, University of Colorado at Denver and Health Sciences Center, Denver, CO, USA.
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111
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Hui J, Oka A, James A, Palmer LJ, Musk AW, Beilby J, Inoko H. A genome-wide association scan for asthma in a general Australian population. Hum Genet 2008; 123:297-306. [PMID: 18253752 DOI: 10.1007/s00439-008-0477-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2007] [Accepted: 01/25/2008] [Indexed: 01/31/2023]
Abstract
To date, almost every chromosome has been implicated in genetic susceptibility to asthma to some degree. When compared with single nucleotide polymorphism, microsatellite markers exhibit high levels of heterozygosity and therefore provide higher statistical power in association. The objective of this study was to perform a genome-wide association study using 23,465 in-house microsatellite markers to detect asthma susceptibility regions in the Busselton population. In this study, three separate pooled DNA screenings yielded 18 markers with significantly different estimated frequencies in the three separate "case and control" pools: each pool consisting of 60 males and 60 females. These markers were evaluated by individual typing in 360 cases and 360 controls. Two markers showed significant differences between cases and controls (P = 0.001 and P = 0.003). Regions surrounding the two markers were subjected to high-density association mapping with a total of 14 additional markers. We were able to confirm and fine map the association in these two regions by typing 14 additional microsatellite markers (1805A09 (D18S0325i), P = 0.002; 1806D05 (D18S0181i), P = 0.001). Each region contains a predicted gene that showed strong associations with asthma. Further studies are underway to characterize the novel candidate asthma susceptibility genes identified in this genome-wide study.
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Affiliation(s)
- J Hui
- Western Australian Institute for Medical Research and UWA Centre for Medical Research, B Block, QEII Medical Centre, The University of Western Australia, Nedlands, WA, 6009, Australia.
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112
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Leehey MA, Berry-Kravis E, Goetz CG, Zhang L, Hall DA, Li L, Rice CD, Lara R, Cogswell J, Reynolds A, Gane L, Jacquemont S, Tassone F, Grigsby J, Hagerman RJ, Hagerman PJ. FMR1 CGG repeat length predicts motor dysfunction in premutation carriers. Neurology 2007; 70:1397-402. [PMID: 18057320 DOI: 10.1212/01.wnl.0000281692.98200.f5] [Citation(s) in RCA: 134] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Fragile X-associated tremor/ataxia syndrome (FXTAS) is a recently described, underrecognized neurodegenerative disorder of aging fragile X mental retardation 1 (FMR1) premutation carriers, particularly men. Core motor features are action tremor, gait ataxia, and parkinsonism. Carriers have expanded CGG repeats (55 to 200); larger expansions cause fragile X syndrome, the most common heritable cause of mental retardation and autism. This study determines whether CGG repeat length correlates with severity and type of motor dysfunction in premutation carriers. METHODS Persons aged >or=50 years with a family history of fragile X syndrome underwent structured videotaping. Movement disorder neurologists, blinded to carrier status, scored the tapes using modified standardized rating scales. CGG repeat length analyses for women incorporated the activation ratio, which measures the percentage of normal active chromosome X alleles. RESULTS Male carriers (n = 54) had significantly worse total motor scores, especially in tremor and ataxia, than age-matched male noncarriers (n = 51). There was a trend toward a difference between women carriers (n = 82) and noncarriers (n = 39). In men, increasing CGG repeat correlated with greater impairment in all motor signs. In women, when activation ratio was considered, increasing CGG correlated with greater ataxia. CONCLUSIONS CGG repeat size is significantly associated with overall motor impairment in premutation carriers. Whereas this association is most pronounced for men and covers overall motor impairment-tremor, ataxia, and parkinsonism-the association exists for ataxia among women carriers. This is the first report of a significant correlation between the premutation status and a motor feature of fragile X-associated tremor/ataxia syndrome in women.
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Affiliation(s)
- M A Leehey
- Department of Neurology, University of Colorado at Denver and Health Sciences Center, Denver, CO 80262, USA.
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