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Shieh M, Amkraut K, Spiridigliozzi GA, Adayev T, Nicholson K, McConkie‐Rosell A, McDonald M, Pennington M, Sebastian S, Lachiewicz AM. High performing male with fragile X syndrome with an unmethylated FMR1 full mutation: The relevance of clinical and genetic correlations. Clin Case Rep 2023; 11:e7371. [PMID: 37361657 PMCID: PMC10290186 DOI: 10.1002/ccr3.7371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 04/28/2023] [Accepted: 05/08/2023] [Indexed: 06/28/2023] Open
Abstract
A high performing male with an unmethylated full mutation in the fragile X messenger ribonucleoprotein 1 (FMR1) gene surpassed our expectations into young adulthood. Although initial genetic findings helped make a correct fragile X syndrome (FXS) determination, the report was insufficient. Ten years later, we repeated and conducted additional genetic and clinical studies to determine whether more information could assist with treatment and counseling. The genetic findings were very consistent with his high functioning and would have enabled us to be more confident about a good developmental outcome had they been available previously. As FXS enters the mainstream of well-understood genetic disorders and technological advancements improve genetic tests, it should be clearer to clinical providers what a full FXS assessment could include to provide high quality information for care. For individuals with FXS who are high functioning, their families and clinical professionals would benefit from knowing more genetic findings, including, most importantly, methylation status, but also the FMR1 protein (FMRP) level and mRNA level. While we now know that obtaining only the CGG repeat number is not always adequate to inform accurate clinical care, future studies are likely to show the benefit of studying other biomarkers, such as mRNA levels.
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Affiliation(s)
- Meg Shieh
- Department of ChemistryBrown UniversityProvidenceRhode IslandUSA
- Department of PediatricsDuke University Health SystemDurhamNorth CarolinaUSA
| | - Keren Amkraut
- Department of PediatricsDuke University Health SystemDurhamNorth CarolinaUSA
| | - Gail A. Spiridigliozzi
- Department of PediatricsDuke University Health SystemDurhamNorth CarolinaUSA
- Department of Psychiatry and Behavioral SciencesDuke University Medical CenterDurhamNorth CarolinaUSA
| | - Tatyana Adayev
- Department of Human GeneticsNew York State Institute for Basic Research in Developmental DisabilitiesNew YorkNew YorkUSA
| | - Kaylea Nicholson
- Department of Communication SciencesDuke University Health CenterDurhamNorth CarolinaUSA
| | | | - Marie McDonald
- Department of PediatricsDuke University Health SystemDurhamNorth CarolinaUSA
| | | | - Siby Sebastian
- Department of PathologyDuke University Health SystemDurhamNorth CarolinaUSA
| | - Ave M. Lachiewicz
- Department of PediatricsDuke University Health SystemDurhamNorth CarolinaUSA
- Department of Psychiatry and Behavioral SciencesDuke University Medical CenterDurhamNorth CarolinaUSA
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Fang Y, Li J, Zhang M, Cheng Y, Wang C, Zhu J. Clinical application value of expanded carrier screening in the population of childbearing age. Eur J Med Res 2023; 28:151. [PMID: 37031186 PMCID: PMC10082524 DOI: 10.1186/s40001-023-01112-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 03/30/2023] [Indexed: 04/10/2023] Open
Abstract
OBJECTIVE The objective of this study was to explore the clinical utility of the implementation of expanded carrier screening (ECS) in Chinese population of childbearing age. MATERIALS AND METHODS Based on capillary electrophoresis, a first-generation sequencing technology, a prospective screening study of carriers of 15 single-gene diseases was carried out in 327 subjects in Anhui Province, including 84 couples and 159 women of childbearing age, the disease carrier rate, types of screened pathogenic genes, and incidence of both partners carrying the same pathogenic genes were summarized and analyzed. RESULTS In 320 people with normal phenotypes who underwent ECS for 15 genetic diseases and 7 spouses who underwent targeted gene sequencing, 65 carriers of at least one disease were detected, with a total carrier rate of 20.31% (65/320). Among the 65 carriers, 81.54% (53/65) carried one genetic variant, 16.92% (11/65) carried two genetic variants, and 1.54% (1/65) carried three genetic variants. In this study, the three diseases with the highest carrier rates were hereditary deafness (8.13%, 26/320), Wilson's disease (4.06%, 13/320), and phenylketonuria (3.13%, 10/320). One high-risk couple (1.19%, 1/84) was detected. CONCLUSIONS It has certain clinical application value to implement ECS in the population of childbearing age in China.
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Affiliation(s)
- Yuqin Fang
- Affiliated Maternity and Child Health Hospital of Anhui Medical University, Hefei, China
- Maternity and Child Health Hospital of Anhui Province, Hefei, China
| | - Jingran Li
- Maternity and Child Health Hospital of Anhui Province, Hefei, China
| | - Miaomiao Zhang
- Maternity and Child Health Hospital of Anhui Province, Hefei, China
| | - Yuan Cheng
- Maternity and Child Health Hospital of Anhui Province, Hefei, China
| | - Chaohong Wang
- Maternity and Child Health Hospital of Anhui Province, Hefei, China
| | - Jiansheng Zhu
- Affiliated Maternity and Child Health Hospital of Anhui Medical University, Hefei, China.
- Maternity and Child Health Hospital of Anhui Province, Hefei, China.
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Cascade health service use in family members following genetic testing in children: a scoping literature review. Eur J Hum Genet 2021; 29:1601-1610. [PMID: 34446836 PMCID: PMC8560854 DOI: 10.1038/s41431-021-00952-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 07/06/2021] [Accepted: 08/12/2021] [Indexed: 12/23/2022] Open
Abstract
Cascade genetic testing is the identification of individuals at risk for a hereditary condition by genetic testing in relatives of people known to possess particular genetic variants. Cascade testing has health system implications, however cascade costs and health effects are not considered in health technology assessments (HTAs) that focus on costs and health consequences in individual patients. Cascade health service use must be better understood to be incorporated in HTA of emerging genetic tests for children. The purpose of this review was to characterise published research related to patterns and costs of cascade health service use by relatives of children with any condition diagnosed through genetic testing. To this end, a scoping literature review was conducted. Citation databases were searched for English-language papers reporting uptake, costs, downstream health service use, or cost-effectiveness of cascade investigations of relatives of children who receive a genetic diagnosis. Included publications were critically appraised, and findings were synthesised. Twenty publications were included. Sixteen had a paediatric proband population; four had a combined paediatric and adult proband population. Uptake of cascade testing varied across diseases, from 37% for cystic fibrosis, 39% to 65% for hypertrophic cardiomyopathy, and 90% for rare monogenic conditions. Two studies evaluated costs. It was concluded that cascade testing in the child-to-parent direction has been reported in a variety of diseases, and that understanding the scope of cascade testing will aid in the design and conduct of HTA of emerging genetic technologies to better inform funding and policy decisions.
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Landowska A, Rzońca S, Bal J, Gos M. [Fragile X syndrome and FMR1-dependent diseases - clinical presentation, epidemiology and molecular background]. DEVELOPMENTAL PERIOD MEDICINE 2018; 22. [PMID: 29641417 PMCID: PMC8522919 DOI: 10.34763/devperiodmed.20182201.1421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Fragile X syndrome (FXS) is the second most common inherited cause of intellectual disability (ID), after Down syndrome. The severity of ID in FXS patients varies and depends mainly on the patient's sex. Besides intellectual disorders, additional symptoms, such as psychomotor delay, a specific behavioral phenotype, or emotional problems are present in FXS patients. In over 99% of the cases, the disease is caused by the presence of a dynamic mutation in the FMR1 gene localized on the X chromosome. Due to the expansion of CGG nucleotides (over 200 repeats), FMR1 gene expression is decreased and results in the significant reduction of the FMRP protein level. The CGG expansion to premutation range (55-200 CGG repeats) is equivalent to the FXS carrier status and may cause FMR1-dependent disorders - fragile X-associated primary ovarian insufficiency (FXPOI) and fragile X-associated tremor/ataxia syndrome (FXTAS). In contrast to FXS, clinical symptoms of these diseases occur later in adulthood. The aim of the article is to present the knowledge about the molecular background and epidemiology of fragile X syndrome and other FMR1-related disorders.
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Affiliation(s)
- Aleksandra Landowska
- Zakład Genetyki Medycznej, Instytut Matki i Dziecka, Warszawa, Polska,Aleksandra Landowska Zakład Genetyki Medycznej, Instytut Matki i Dziecka ul. Kasprzaka 17a, 01-211 Warszawa tel. (+48 22) 327-71-76
| | - Sylwia Rzońca
- Zakład Genetyki Medycznej, Instytut Matki i Dziecka, Warszawa, Polska
| | - Jerzy Bal
- Zakład Genetyki Medycznej, Instytut Matki i Dziecka, Warszawa, Polska
| | - Monika Gos
- Zakład Genetyki Medycznej, Instytut Matki i Dziecka, Warszawa, Polska
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Wotton T, Wiley V, Bennetts B, Christie L, Wilcken B, Jenkins G, Rogers C, Boyle J, Field M. Are We Ready for Fragile X Newborn Screening Testing?-Lessons Learnt from a Feasibility Study. Int J Neonatal Screen 2018; 4:9. [PMID: 33072935 PMCID: PMC7548904 DOI: 10.3390/ijns4010009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Accepted: 01/23/2018] [Indexed: 12/17/2022] Open
Abstract
Fragile X syndrome (FXS) is the most prevalent heritable cause of cognitive impairment but is not yet included in a newborn screening (NBS) program within Australia. This paper aims to assess the feasibility and reliability of population screening for FXS using a pilot study in one hospital. A total of 1971 mothers consented for 2000 newborns to be tested using routine NBS dried blood spot samples. DNA was extracted and a modified PCR assay with a chimeric CGG primer was used to detect fragile X alleles in both males and females in the normal, premutation, and full mutation ranges. A routine PCR-based fragile X assay was run in parallel to validate the chimeric primer assay. Babies with CGG repeat number ≥59 were referred for family studies. One thousand nine hundred and ninety NBS samples had a CGG repeat number less than 55 (1986 < 50); 10 had premutation alleles >54 CGG repeats (1/123 females and 1/507 males). There was complete concordance between the two PCR-based assays. A recent review revealed no clinically identified cases in the cohort up to 5 years later. The cost per test was $AUD19. Fragile X status can be determined on routine NBS samples using the chimeric primer assay. However, whilst this assay may not be considered cost-effective for population screening, it could be considered as a second-tier assay to a developed immunoassay for fragile X mental retardation protein (FMRP).
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Affiliation(s)
- Tiffany Wotton
- The NSW Newborn Screening Programme, The Children’s Hospital at Westmead, Westmead, NSW 2145, Australia
- Correspondence:
| | - Veronica Wiley
- The NSW Newborn Screening Programme, The Children’s Hospital at Westmead, Westmead, NSW 2145, Australia
- Disciplines of Paediatrics & Child Health and Genetic Medicine, The University of Sydney, Sydney, NSW 2006, Australia
| | - Bruce Bennetts
- Disciplines of Paediatrics & Child Health and Genetic Medicine, The University of Sydney, Sydney, NSW 2006, Australia
- Sydney Genome Diagnostics—Department of Molecular Genetics, The Children’s Hospital at Westmead, Westmead, NSW 2145, Australia
| | - Louise Christie
- Genetics of Learning Disability, Hunter Genetics, Waratah, NSW 2298, Australia
| | - Bridget Wilcken
- The NSW Newborn Screening Programme, The Children’s Hospital at Westmead, Westmead, NSW 2145, Australia
- Disciplines of Paediatrics & Child Health and Genetic Medicine, The University of Sydney, Sydney, NSW 2006, Australia
| | - Gemma Jenkins
- Sydney Genome Diagnostics—Department of Molecular Genetics, The Children’s Hospital at Westmead, Westmead, NSW 2145, Australia
| | - Carolyn Rogers
- Genetics of Learning Disability, Hunter Genetics, Waratah, NSW 2298, Australia
| | - Jackie Boyle
- Genetics of Learning Disability, Hunter Genetics, Waratah, NSW 2298, Australia
| | - Michael Field
- Genetics of Learning Disability, Hunter Genetics, Waratah, NSW 2298, Australia
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Abstract
The FMR1 premutation confers a 40–60% risk for males of developing a neurodegenerative disease called the Fragile X-associated Tremor Ataxia Syndrome (FXTAS). FXTAS is a late-onset disease that primarily involves progressive symptoms of tremor and ataxia, as well as cognitive decline that can develop into dementia in some patients. At present, it is not clear whether changes to brain function are detectable in motor regions prior to the onset of frank symptomatology. The present study therefore aimed to utilize an fMRI motor task for the first time in an asymptomatic premutation population. Premutation carriers without a diagnosis of FXTAS (n = 17) and a group of healthy male controls (n = 17), with an age range of 24–68 years old, were recruited for this cross-sectional study. This study utilized neuroimaging, molecular and clinical measurements, employing an fMRI finger-tapping task with a block design consisting of sequential finger-tapping, random finger-tapping and rest conditions. The imaging analysis contrasted the sequential and random conditions to investigate activation changes in response to a change in task demand. Additionally, measurements were obtained of participant tremor, co-ordination and balance using the CATSYS-2000 system and measures of FMR1 mRNA were quantified from peripheral blood samples using quantitative real-time PCR methodology. Premutation carriers demonstrated significantly less cerebellar activation than controls during sequential versus random finger tapping (FWEcorr < 0.001). In addition, there was a significant age by group interaction in the hippocampus, inferior parietal cortex and temporal cortex originating from a more negative relationship between brain activation and age in the carrier group compared to the controls (FWEcorr < 0.001). Here, we present for the first time functional imaging-based evidence for early movement-related neurodegeneration in Fragile X premutation carriers. These changes pre-exist the diagnosis of FXTAS and are greatest in older carriers suggesting that they may be indicative of FXTAS vulnerability. The authors present a cross-sectional fMRI study in male carriers of the FMR1 premutation Carriers show decreased BOLD activation at the cerebellum in response to change in task demand in a finger-tapping task Carriers exhibit a group x age interaction of BOLD response in the temporoparietal area These changes pre-exist the diagnosis of the Fragile X-associated Tremor/Ataxia Syndrome (FXTAS)
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Wheeler A, Raspa M, Hagerman R, Mailick M, Riley C. Implications of the FMR1 Premutation for Children, Adolescents, Adults, and Their Families. Pediatrics 2017; 139:S172-S182. [PMID: 28814538 PMCID: PMC5621635 DOI: 10.1542/peds.2016-1159d] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/24/2017] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND AND OBJECTIVES Given the nature of FMR1 gene expansions, most biological mothers, and often multiple other family members of children with fragile X syndrome (FXS), will have a premutation, which may increase individual and family vulnerabilities. This article summarizes important gaps in knowledge and notes potential implications for pediatric providers with regard to developmental and medical risks for children and adolescents with an FMR1 premutation, including possible implications into adulthood. METHODS A structured electronic literature search was conducted on FMR1 pre- and full mutations, yielding a total of 306 articles examined. Of these, 116 focused primarily on the premutation and are included in this review. RESULTS Based on the literature review, 5 topic areas are discussed: genetics and epidemiology; phenotypic characteristics of individuals with the premutation; implications for carrier parents of children with FXS; implications for the extended family; and implications for pediatricians. CONCLUSIONS Although the premutation phenotype is typically less severe in clinical presentation than in FXS, premutation carriers are much more common and are therefore more likely to be seen in a typical pediatric practice. In addition, there is a wide range of medical, cognitive/developmental, and psychiatric associated features that individuals with a premutation are at increased risk for having, which underscores the importance of awareness on the part of pediatricians in identifying and monitoring premutation carriers and recognizing the impact this identification may have on family members.
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Affiliation(s)
- Anne Wheeler
- RTI International, Research Triangle Park, North Carolina;
| | - Melissa Raspa
- RTI International, Research Triangle Park, North Carolina
| | - Randi Hagerman
- MIND Institute, University of California at Davis, Sacramento, California
| | - Marsha Mailick
- Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin; and
| | - Catharine Riley
- National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia
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Bailey DB, Berry-Kravis E, Gane LW, Guarda S, Hagerman R, Powell CM, Tassone F, Wheeler A. Fragile X Newborn Screening: Lessons Learned From a Multisite Screening Study. Pediatrics 2017; 139:S216-S225. [PMID: 28814542 DOI: 10.1542/peds.2016-1159h] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/24/2017] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Delays in the diagnosis of children with fragile X syndrome (FXS) suggest the possibility of newborn screening as a way to identify children earlier. However, FXS does not have a proven treatment that must be provided early, and ethical concerns have been raised about the detection of infants who are carriers. This article summarizes major findings from a multisite, prospective, longitudinal pilot screening study. METHODS Investigators in North Carolina, California, and Illinois collaborated on a study in which voluntary screening for FXS was offered to parents in 3 birthing hospitals. FXS newborn screening was offered to >28 000 families to assess public acceptance and determine whether identification of babies resulted in any measurable harms or adverse events. Secondary goals were to determine the prevalence of FMR1 carrier gene expansions, study the consent process, and describe early development and behavior of identified children. RESULTS A number of publications have resulted from the project. This article summarizes 10 "lessons learned" about the consent process, reasons for accepting and declining screening, development and evaluation of a decision aid, prevalence of carriers, father participation in consent, family follow-up, and maternal reactions to screening. CONCLUSIONS The project documented public acceptance of screening as well as the challenges inherent in obtaining consent in the hospital shortly after birth. Collectively, the study provides answers to a number of questions that now set the stage for a next generation of research to determine the benefits of earlier identification for children and families.
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Affiliation(s)
- Donald B Bailey
- Center for Newborn Screening, Ethics, and Disability Studies, RTI International, Research Triangle Park, North Carolina;
| | | | - Louise W Gane
- MIND Institute, University of California at Davis, Sacramento, California; and
| | - Sonia Guarda
- Department of Pediatrics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Randi Hagerman
- MIND Institute, University of California at Davis, Sacramento, California; and
| | - Cynthia M Powell
- Department of Pediatrics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Flora Tassone
- MIND Institute, University of California at Davis, Sacramento, California; and
| | - Anne Wheeler
- Center for Newborn Screening, Ethics, and Disability Studies, RTI International, Research Triangle Park, North Carolina
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Molecular Correlates and Recent Advancements in the Diagnosis and Screening of FMR1-Related Disorders. Genes (Basel) 2016; 7:genes7100087. [PMID: 27754417 PMCID: PMC5083926 DOI: 10.3390/genes7100087] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 10/06/2016] [Accepted: 10/08/2016] [Indexed: 12/12/2022] Open
Abstract
Fragile X syndrome (FXS) is the most common monogenic cause of intellectual disability and autism. Molecular diagnostic testing of FXS and related disorders (fragile X-associated primary ovarian insufficiency (FXPOI) and fragile X-associated tremor/ataxia syndrome (FXTAS)) relies on a combination of polymerase chain reaction (PCR) and Southern blot (SB) for the fragile X mental retardation 1 (FMR1) CGG-repeat expansion and methylation analyses. Recent advancements in PCR-based technologies have enabled the characterization of the complete spectrum of CGG-repeat mutation, with or without methylation assessment, and, as a result, have reduced our reliance on the labor- and time-intensive SB, which is the gold standard FXS diagnostic test. The newer and more robust triplet-primed PCR or TP-PCR assays allow the mapping of AGG interruptions and enable the predictive analysis of the risks of unstable CGG expansion during mother-to-child transmission. In this review, we have summarized the correlation between several molecular elements, including CGG-repeat size, methylation, mosaicism and skewed X-chromosome inactivation, and the extent of clinical involvement in patients with FMR1-related disorders, and reviewed key developments in PCR-based methodologies for the molecular diagnosis of FXS, FXTAS and FXPOI, and large-scale (CGG)n expansion screening in newborns, women of reproductive age and high-risk populations.
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Family Communication and Cascade Testing for Fragile X Syndrome. J Genet Couns 2016; 25:1075-84. [DOI: 10.1007/s10897-016-9940-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 02/18/2016] [Indexed: 10/22/2022]
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Famula J, Basuta K, Gane LW, Hagerman RJ, Tassone F. Identification of a male with fragile X syndrome through newborn screening. Intractable Rare Dis Res 2015; 4:198-202. [PMID: 26668780 PMCID: PMC4660861 DOI: 10.5582/irdr.2015.01031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
A pilot newborn screening (NBS) study for fragile X syndrome was recently conducted at the University of California, Davis Medical Center. The screening study identified a case of a male with the full mutation completely methylated and no detectable expression of the fragile X mental retardation-1 (FMR1) gene. The patient was initially seen in clinic at the MIND Institute, for medical follow-up and a genetic counseling session at the chronological age of 3 months. Since then, he has been seen in clinic every six months for follow up, medical examination and developmental assessments. Longitudinally administered developmental testing of the infant has revealed persistent delays in development, consistent with fragile X syndrome. Cascade testing revealed that the patient's mother and two siblings also have the full mutation. The patient has been receiving speech and language therapy, combined with physical and occupational therapies on a weekly basis since the age of one year. He is currently being treated with 2.5 mg of sertraline, which has been demonstrated to be helpful for improving language in young children with the syndrome.
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Affiliation(s)
- Jessica Famula
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California Davis, Sacramento, USA
| | - Kirin Basuta
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California Davis, Sacramento, USA
| | - Louise W. Gane
- MIND Institute, University of California, Davis, Medical Center, Sacramento, USA
| | - Randi J. Hagerman
- MIND Institute, University of California, Davis, Medical Center, Sacramento, USA
- Department of Pediatrics, University of California at Davis, Sacramento, USA
| | - Flora Tassone
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California Davis, Sacramento, USA
- MIND Institute, University of California, Davis, Medical Center, Sacramento, USA
- Address correspondence to: Dr. Flora Tassone, Department of Biochemistry and Molecular Medicine, 2700 Stockton Blvd, Suite 2102, Sacramento, CA 95817, USA; MIND Institute, 2805 50th Street Sacramento, CA 95817, USA. E-mail:
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12
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Bailey DB, Wheeler A, Berry-Kravis E, Hagerman R, Tassone F, Powell CM, Roche M, Gane LW, Sideris J. Maternal Consequences of the Detection of Fragile X Carriers in Newborn Screening. Pediatrics 2015; 136:e433-40. [PMID: 26169437 PMCID: PMC4516945 DOI: 10.1542/peds.2015-0414] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/19/2015] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVES The possibility of newborn screening for fragile X syndrome is complicated by the potential for identifying premutation carriers. Although knowing the child's carrier status has potential benefits, the possibility of late-onset disorders in carrier children and their parents raises concerns about whether such information would be distressing to parents and potentially more harmful than helpful. This study sought to answer this question by offering voluntary fragile X screening to new parents and returning results for both the full mutation and premutation FMR1 gene expansions. We tested the assumption that such information could lead to adverse mental health outcomes or decision regret. We also wanted to know if child age and spousal support were associated with the outcomes of interest. METHODS Eighteen mothers of screen-positive infants with the premutation and 15 comparison mothers completed a battery of assessments of maternal anxiety, postpartum depression, stress, family quality of life, decision regret, and spousal support. The study was longitudinal, with an average of 3 assessments per mother. RESULTS The premutation group was not statistically different from the comparison group on measures of anxiety, depression, stress, or quality of life. A subset of mothers experienced clinically significant anxiety and decision regret, but factors associated with these outcomes could not be identified. Greater spousal support was generally associated with more positive outcomes. CONCLUSIONS Although we did not find evidence of significant adverse events, disclosure of newborn carrier status remains an important consideration in newborn screening policy.
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Affiliation(s)
- Donald B Bailey
- Social, Statistical, and Environmental Sciences, RTI International, Research Triangle Park, North Carolina;
| | - Anne Wheeler
- Social, Statistical, and Environmental Sciences, RTI International, Research Triangle Park, North Carolina
| | - Elizabeth Berry-Kravis
- Departments of Pediatrics and Neurologic Sciences, Rush University Medical Center, Chicago, Illinois
| | - Randi Hagerman
- Department of Pediatrics, M.I.N.D. Institute, University of California at Davis Medical Center, Sacramento, California
| | - Flora Tassone
- Department of Pediatrics, M.I.N.D. Institute, University of California at Davis Medical Center, Sacramento, California
| | - Cynthia M Powell
- Department of Pediatrics and Genetics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Myra Roche
- Department of Pediatrics and Genetics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Louise W Gane
- M.I.N.D. Institute, University of California at Davis Medical Center, Sacramento, California
| | - John Sideris
- Frank Porter Graham Child Development Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
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Therrell BL, Padilla CD, Loeber JG, Kneisser I, Saadallah A, Borrajo GJC, Adams J. Current status of newborn screening worldwide: 2015. Semin Perinatol 2015; 39:171-87. [PMID: 25979780 DOI: 10.1053/j.semperi.2015.03.002] [Citation(s) in RCA: 353] [Impact Index Per Article: 39.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Newborn screening describes various tests that can occur during the first few hours or days of a newborn's life and have the potential for preventing severe health problems, including death. Newborn screening has evolved from a simple blood or urine screening test to a more comprehensive and complex screening system capable of detecting over 50 different conditions. While a number of papers have described various newborn screening activities around the world, including a series of papers in 2007, a comprehensive review of ongoing activities since that time has not been published. In this report, we divide the world into 5 regions (North America, Europe, Middle East and North Africa, Latin America, and Asia Pacific), assessing the current NBS situation in each region and reviewing activities that have taken place in recent years. We have also provided an extensive reference listing and summary of NBS and health data in tabular form.
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Affiliation(s)
- Bradford L Therrell
- National Newborn Screening and Genetics Resource Center (NNSGRC), Austin, TX; Department of Pediatrics, University of Texas Health Science Center at San Antonio, San Antonio, TX.
| | - Carmencita David Padilla
- College of Medicine, University of the Philippines Manila, Manila, Philippines; Newborn Screening Reference Center, National Institutes of Health (Philippines), Manila, Ermita, Philippines
| | - J Gerard Loeber
- International Society for Neonatal Screening, Bilthoven, Netherlands
| | - Issam Kneisser
- Newborn Screening Unit, Medical Genetic Unit, Faculty of Medicine, Saint Joseph University, Beirut, Lebanon
| | - Amal Saadallah
- Newborn Screening and Biochemical Genetics Laboratory, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Gustavo J C Borrajo
- Programa de Detección de Errores Congénitos, Fundación Bioquímica Argentina, La Plata, Argentina
| | - John Adams
- Canadian Organization for Rare Disorders, Toronto, Ontario, Canada
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Hagerman PJ, Hagerman RJ. Fragile X-associated tremor/ataxia syndrome. Ann N Y Acad Sci 2015; 1338:58-70. [PMID: 25622649 PMCID: PMC4363162 DOI: 10.1111/nyas.12693] [Citation(s) in RCA: 120] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 12/04/2014] [Accepted: 12/18/2014] [Indexed: 12/20/2022]
Abstract
Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder that affects some but not all carriers of small, noncoding CGG-repeat expansions (55-200 repeats; premutation) within the fragile X gene (FMR1). Principal features of FXTAS include intention tremor, cerebellar ataxia, Parkinsonism, memory and executive function deficits, autonomic dysfunction, brain atrophy with white matter disease, and cognitive decline. Although FXTAS was originally considered to be confined to the premutation range, rare individuals with a gray zone (45-54 repeats) or an unmethylated full mutation (>200 repeats) allele have now been described, the constant feature of the disorder remaining the requirement for FMR1 expression, in contradistinction to the gene silencing mechanism of fragile X syndrome. Although transcriptional activity is required for FXTAS pathogenesis, the specific trigger(s) for FXTAS pathogenesis remains elusive, highlighting the need for more research in this area. This need is underscored by recent neuroimaging findings of changes in the central nervous system that consistently appear well before the onset of clinical symptoms, thus creating an opportunity to delay or prevent the appearance of FXTAS.
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Affiliation(s)
- Paul J Hagerman
- Department of Biochemistry and Molecular Medicine, University of California , Davis , School of Medicine, Davis, California; The MIND Institute, University of California , Davis , Health System, Sacramento, California
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15
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Marsiglia JDC, Pereira AC. Hypertrophic cardiomyopathy: how do mutations lead to disease? Arq Bras Cardiol 2014; 102:295-304. [PMID: 24714796 PMCID: PMC3987320 DOI: 10.5935/abc.20140022] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Accepted: 08/23/2013] [Indexed: 12/13/2022] Open
Abstract
Hypertrophic cardiomyopathy (HCM) is the most common monogenic genetic cardiac
disease, with an estimated prevalence of 1:500 in the general population. Clinically,
HCM is characterized by hypertrophy of the left ventricle (LV) walls, especially the
septum, usually asymmetric, in the absence of any cardiac or systemic disease that
leads to a secondary hypertrophy. The clinical course of the disease has a large
inter- and intrafamilial heterogeneity, ranging from mild symptoms of heart failure
late in life to the onset of sudden cardiac death at a young age and is caused by a
mutation in one of the genes that encode a protein from the sarcomere, Z-disc or
intracellular calcium modulators. Although many genes and mutations are already known
to cause HCM, the molecular pathways that lead to the phenotype are still unclear.
This review focus on the molecular mechanisms of HCM, the pathways from mutation to
clinical phenotype and how the disease's genotype correlates with phenotype.
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Affiliation(s)
- Júlia Daher Carneiro Marsiglia
- Mailing Address: Júlia Daher Carneiro Marsiglia, Av. Dr. Enéas de
Carvalho Aguiar, 44, Cerqueira César. Postal Code 05403- 900, São Paulo, SP - Brazil.
E-mail: ;
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Gallego PK, Burris JL, Rivera SM. Visual motion processing deficits in infants with the fragile X premutation. J Neurodev Disord 2014; 6:29. [PMID: 25093044 PMCID: PMC4121307 DOI: 10.1186/1866-1955-6-29] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Accepted: 07/11/2014] [Indexed: 01/31/2023] Open
Abstract
Background Fragile X syndrome (FXS) results from a trinucleotide repeat expansion (full mutation >200 cytosine-guanine-guanine (CGG) repeats) in the FMR1 gene, leading to a reduction or absence of the gene’s protein product, fragile X mental retardation protein (FMRP), ultimately causing cognitive and behavioral impairments that are characteristic of the syndrome. In our previous work with infants and toddlers with FXS, we have been able to describe much about their cognitive and visual processing abilities. In light of recent work on the mild cognitive deficits and functional and structural brain differences that are present in adults with the fragile X (FX) premutation, in the present study we examined whether some of the low-level visual processing deficits we have observed in infants with FXS would also be present in infants with the FX premutation (55–200 CGG repeats). Methods We chose a contrast detection task using second-order motion stimuli on which infants with FXS previously showed significantly increased detection thresholds (Vision Res 48:1471–1478, 2008). Critically, we also included a developmental delay comparison group of infants with Down syndrome (DS), who were matched to infants with FXS on both chronological and mental age, to speak to the question of whether this second-order motion processing deficit is a FX-specific phenomenon. Results As reported previously, infants with the FX full mutation showed motion contrast detection threshold levels that were significantly higher than age-matched typically developing control infants. Strikingly, the motion detection contrast levels of FX premutation infants were also significantly higher than typically developing (TD) infants and not significantly different from the group of infants with FXS or with DS. Conclusions These results, which are in keeping with a growing body of evidence on the mild cognitive and perceptual processing deficits and functional and structural brain differences that are present in adults and older children with the FX premutation, underscore the pressing need to study and describe the processing capabilities of infants and toddlers with the FX premutation.
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Affiliation(s)
- Pamela K Gallego
- Department of Psychology, University of California Davis, Davis, CA 95618, USA ; Center for Mind and Brain, University of California Davis, 202 Cousteau Place, Suite 250, Davis, CA 95618, USA
| | - Jessica L Burris
- Department of Psychology, University of California Davis, Davis, CA 95618, USA ; Center for Mind and Brain, University of California Davis, 202 Cousteau Place, Suite 250, Davis, CA 95618, USA
| | - Susan M Rivera
- Department of Psychology, University of California Davis, Davis, CA 95618, USA ; Center for Mind and Brain, University of California Davis, 202 Cousteau Place, Suite 250, Davis, CA 95618, USA ; M.I.N.D. Institute, University of California Medical Center, Sacramento, CA 95817, USA
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17
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Visootsak J, Hipp H, Clark H, Berry-Kravis E, Anderson T, Laney D. Climbing the branches of a family tree: diagnosis of fragile X syndrome. J Pediatr 2014; 164:1292-5. [PMID: 24612903 PMCID: PMC4035419 DOI: 10.1016/j.jpeds.2014.01.051] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Revised: 12/30/2013] [Accepted: 01/24/2014] [Indexed: 11/18/2022]
Abstract
OBJECTIVE To determine the average number of family members diagnosed with a Fragile X Mental Retardation-1 (FMR1) mutation after a proband receives the initial diagnosis of fragile X syndrome (FXS). STUDY DESIGN We reviewed pedigrees of families who had been evaluated at the Fragile X Syndrome Center at Emory University in Atlanta, Georgia. Through these pedigrees, we determined the number of additional family members diagnosed as FMR1 premutation carriers or with full mutation FXS after the initial diagnosis in each proband. RESULTS The fragile X pedigree review identified 176 probands, including 108 males (61%) and 68 females (39%). A total of 785 family members were diagnosed with expanded fragile X alleles, including 278 males (35%) and 507 females (65%). These family members included 227 individuals with full mutation FXS (219 males and 8 females) and 558 premutation carriers (59 males and 499 females). After the initial diagnosis of a proband with FXS, on average at least 5 additional family members were diagnosed with an FMR1 mutation. CONCLUSION Our findings confirm that obtaining a detailed family history after diagnosis of a proband with FXS is likely to identify multiple family members with FMR1 mutations. It is important that the pediatrician or other health care provider making a diagnosis of FXS recognize the value of a detailed family history for timely diagnosis and treatment of additional individuals who may be FMR1 premutation carriers or have full mutation FXS.
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Affiliation(s)
| | - Heather Hipp
- Department of Human Genetics, Emory University, Atlanta, GA
| | - Heather Clark
- Department of Human Genetics, Emory University, Atlanta, GA
| | - Elizabeth Berry-Kravis
- Departments of Pediatrics, Neurological Sciences, and Biochemistry, Rush University Medical Center, Chicago, IL
| | - Tovi Anderson
- Department of Human Genetics, Emory University, Atlanta, GA
| | - Dawn Laney
- Department of Human Genetics, Emory University, Atlanta, GA
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Lozano R, Hare EB, Hagerman RJ. Modulation of the GABAergic pathway for the treatment of fragile X syndrome. Neuropsychiatr Dis Treat 2014; 10:1769-79. [PMID: 25258535 PMCID: PMC4172237 DOI: 10.2147/ndt.s42919] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Fragile X syndrome (FXS) is the most common genetic cause of intellectual disability and the most common single-gene cause of autism. It is caused by mutations on the fragile X mental retardation gene (FMR1) and lack of fragile X mental retardation protein, which in turn, leads to decreased inhibition of translation of many synaptic proteins. The metabotropic glutamate receptor (mGluR) hypothesis states that the neurological deficits in individuals with FXS are due mainly to downstream consequences of overstimulation of the mGluR pathway. The main efforts have focused on mGluR5 targeted treatments; however, investigation on the gamma-aminobutyric acid (GABA) system and its potential as a targeted treatment is less emphasized. The fragile X mouse models (Fmr1-knock out) show decreased GABA subunit receptors, decreased synthesis of GABA, increased catabolism of GABA, and overall decreased GABAergic input in many regions of the brain. Consequences of the reduced GABAergic input in FXS include oversensitivity to sensory stimuli, seizures, and anxiety. Deficits in the GABA receptors in different regions of the brain are associated with behavioral and attentional processing deficits linked to anxiety and autistic behaviors. The understanding of the neurobiology of FXS has led to the development of targeted treatments for the core behavioral features of FXS, which include social deficits, inattention, and anxiety. These symptoms are also observed in individuals with autism and other neurodevelopmental disorders, therefore the targeted treatments for FXS are leading the way in the treatment of other neurodevelopmental syndromes and autism. The GABAergic system in FXS represents a target for new treatments. Herein, we discuss the animal and human trials of GABAergic treatment in FXS. Arbaclofen and ganaxolone have been used in individuals with FXS. Other potential GABAergic treatments, such as riluzole, gaboxadol, tiagabine, and vigabatrin, will be also discussed. Further studies are needed to determine the safety and efficacy of GABAergic treatments for FXS.
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Affiliation(s)
- Reymundo Lozano
- MIND Institute, UC Davis Medical Center, Sacramento, CA, USA ; Department of Pediatrics, UC Davis Medical Center, Sacramento, CA, USA
| | - Emma B Hare
- MIND Institute, UC Davis Medical Center, Sacramento, CA, USA ; Department of Pediatrics, UC Davis Medical Center, Sacramento, CA, USA
| | - Randi J Hagerman
- MIND Institute, UC Davis Medical Center, Sacramento, CA, USA ; Department of Pediatrics, UC Davis Medical Center, Sacramento, CA, USA
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Alfaro MP, Cohen M, Vnencak-Jones CL. Maternal FMR1 premutation allele expansion and contraction in fraternal twins. Am J Med Genet A 2013; 161A:2620-5. [PMID: 23949867 DOI: 10.1002/ajmg.a.36123] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Accepted: 06/10/2013] [Indexed: 11/11/2022]
Abstract
Fragile X syndrome results from an expansion of the CGG trinucleotide repeat in the 5' untranslated region of the Fragile X Mental Retardation 1 (FMR1) gene. Expansion of a maternal premutation allele is the mechanism by which a full mutation allele arises; contraction of a maternal premutation allele is rare. Here we report on both an expansion and contraction of a maternal FMR1 premutation allele in fraternal twins. The propositus was the product of a 29-week gestation twin pregnancy and was referred for FMR1 testing due to developmental delay. A FMR1 full mutation with complete methylation was observed on Southern blot analysis. Evaluation of the maternal FMR1 gene by PCR revealed a normal and premutation allele with CGG repeat numbers of 30 and 93, respectively. Subsequent FMR1 testing on the twin sister of the propositus detected CGG repeat numbers of 30 and 54. The FMR1 CGG repeat number of the reproductive partner was 30. The FMR1 CGG repeat 30 allele in the twin sister was determined to be of paternal origin and the FMR1 allele with a CGG repeat number of 54 was of maternal origin. This observation is particularly interesting not only because of the concomitant donation of a FMR1 expanded and contracted premutation allele in a twin pregnancy but also because of the significant degree of contraction (39 repeats) of the maternal premutation allele.
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Affiliation(s)
- Maria P Alfaro
- Department of Pathology, Microbiology and Immunology, Nashville, Tennessee
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Transmission of an FMR1 premutation allele in a large family identified through newborn screening: the role of AGG interruptions. J Hum Genet 2013; 58:553-9. [PMID: 23739124 DOI: 10.1038/jhg.2013.50] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Revised: 04/02/2013] [Accepted: 04/21/2013] [Indexed: 12/19/2022]
Abstract
The CGG repeat within the premutation range in the fragile X mental retardation 1 (FMR1) gene can lead to neurodegenerative disorders and intellectual disabilities. An increase in size upon the transmission from parent to child is more likely to occur for larger alleles and without AGG interruptions. We describe the molecular structure and the transmission of an FMR1 premutation allele in a multigenerational family, identified through newborn screening for fragile X syndrome. Transmission of the premutation allele was traced through five generations in 14 of the 23 individuals who were genotyped through cascade testing. Allele size instability during transmission was observed, but no expansions to a full mutation were detected. Clinical and molecular characterizations of the participants lead to the diagnosis of fragile X-associated tremor ataxia syndrome in one subject identified as a premutation carrier. A gradual small increase in the size of the premutation allele was observed during transmission through five generations. The relative stability is likely due to the presence of two AGGs within the allele. The detection of AGG interruptions within the premutation alleles is important in genetic counseling, to better predict the risk of expansion during transmission from a premutation to a full-mutation allele.
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Genetic defects behind fragile X-related disorders more common: researchers find the incidence of one type of FMR1 allele double its previous estimate in males. Am J Med Genet A 2013; 161A:x-xi. [PMID: 23520123 DOI: 10.1002/ajmg.a.35948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Tassone F, Iong KP, Tong TH, Lo J, Gane LW, Berry-Kravis E, Nguyen D, Mu LY, Laffin J, Bailey DB, Hagerman RJ. FMR1 CGG allele size and prevalence ascertained through newborn screening in the United States. Genome Med 2012; 4:100. [PMID: 23259642 PMCID: PMC4064316 DOI: 10.1186/gm401] [Citation(s) in RCA: 225] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2012] [Revised: 11/19/2012] [Accepted: 12/21/2012] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Population screening for FMR1 mutations has been a topic of considerable discussion since the FMR1 gene was identified in 1991. Advances in understanding the molecular basis of fragile X syndrome (FXS) and in genetic testing methods have led to new, less expensive methodology to use for large screening endeavors. A core criterion for newborn screening is an accurate understanding of the public health burden of a disease, considering both disease severity and prevalence rate. This article addresses this need by reporting prevalence rates observed in a pilot newborn screening study for FXS in the US. METHODS Blood spot screening of 14,207 newborns (7,312 males and 6,895 females) was conducted in three birthing hospitals across the United States beginning in November 2008, using a PCR-based approach. RESULTS The prevalence of gray zone alleles was 1:66 females and 1:112 males, while the prevalence of a premutation was 1:209 females and 1:430 males. Differences in prevalence rates were observed among the various ethnic groups; specifically higher frequency for gray zone alleles in males was observed in the White group compared to the Hispanic and African-American groups. One full mutation male was identified (>200 CGG repeats). CONCLUSIONS The presented pilot study shows that newborn screening in fragile X is technically feasible and provides overall prevalence of the premutation and gray zone alleles in the USA, suggesting that the prevalence of the premutation, particularly in males, is higher than has been previously reported.
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Affiliation(s)
- Flora Tassone
- Department of Biochemistry and Molecular Medicine, UC Davis, Sacramento, CA 95817, USA
- MIND Institute, UC Davis Medical Center, Sacramento, CA 95817, USA
| | - Ka Pou Iong
- Department of Biochemistry and Molecular Medicine, UC Davis, Sacramento, CA 95817, USA
| | - Tzu-Han Tong
- Department of Biochemistry and Molecular Medicine, UC Davis, Sacramento, CA 95817, USA
| | - Joyce Lo
- Department of Biochemistry and Molecular Medicine, UC Davis, Sacramento, CA 95817, USA
| | - Louise W Gane
- MIND Institute, UC Davis Medical Center, Sacramento, CA 95817, USA
| | - Elizabeth Berry-Kravis
- Department of Pediatrics, Neurological Sciences, and Biochemistry, Rush University Medical Center, Chicago, IL 60612, USA
| | - Danh Nguyen
- Division of Biostatistics, UC Davis, Davis, CA 95616, USA
| | - Lisa Y Mu
- Division of Biostatistics, UC Davis, Davis, CA 95616, USA
| | - Jennifer Laffin
- Department of Pediatrics, University of Wisconsin, Madison, WI 53706, USA
| | - Don B Bailey
- RTI International, Research Triangle Park, NC 27709, USA
| | - Randi J Hagerman
- MIND Institute, UC Davis Medical Center, Sacramento, CA 95817, USA
- Department of Pediatrics, UC Davis, Sacramento, CA 95817, USA
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