1
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Noble KG, Houston SM, Brito NH, Bartsch H, Kan E, Kuperman JM, Akshoomoff N, Amaral DG, Bloss CS, Libiger O, Schork NJ, Murray SS, Casey BJ, Chang L, Ernst TM, Frazier JA, Gruen JR, Kennedy DN, Van Zijl P, Mostofsky S, Kaufmann WE, Kenet T, Dale AM, Jernigan TL, Sowell ER. Family income, parental education and brain structure in children and adolescents. Nat Neurosci 2015; 18:773-8. [PMID: 25821911 PMCID: PMC4414816 DOI: 10.1038/nn.3983] [Citation(s) in RCA: 758] [Impact Index Per Article: 75.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 02/27/2015] [Indexed: 01/18/2023]
Abstract
Socioeconomic disparities are associated with differences in cognitive development. The extent to which this translates to disparities in brain structure is unclear. Here, we investigated relationships between socioeconomic factors and brain morphometry, independently of genetic ancestry, among a cohort of 1099 typically developing individuals between 3 and 20 years. Income was logarithmically associated with brain surface area. Specifically, among children from lower income families, small differences in income were associated with relatively large differences in surface area, whereas, among children from higher income families, similar income increments were associated with smaller differences in surface area. These relationships were most prominent in regions supporting language, reading, executive functions and spatial skills; surface area mediated socioeconomic differences in certain neurocognitive abilities. These data indicate that income relates most strongly to brain structure among the most disadvantaged children. Potential implications are discussed.
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Research Support, Non-U.S. Gov't |
10 |
758 |
2
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Abstract
CONTEXT Autism most commonly appears by 2 to 3 years of life, at which time the brain is already abnormally large. This raises the possibility that brain overgrowth begins much earlier, perhaps before the first clinically noticeable behavioral symptoms. OBJECTIVES To determine whether pathological brain overgrowth precedes the first clinical signs of autism spectrum disorder (ASD) and whether the rate of overgrowth during the first year is related to neuroanatomical and clinical outcome in early childhood. DESIGN, SETTING, AND PARTICIPANTS Head circumference (HC), body length, and body weight measurements during the first year were obtained from the medical records of 48 children with ASD aged 2 to 5 years who had participated in magnetic resonance imaging studies. Of these children, 15 (longitudinal group) had measurements at 4 periods during infancy: birth, 1 to 2 months, 3 to 5 months, and 6 to 14 months; and 33 (partial HC data group) had measurements at birth and 6 to 14 months (n = 7), and at birth only (n = 28). MAIN OUTCOME MEASURES Age-related changes in infants with ASD who had multiple-age measurements, and the relationship of these changes to brain anatomy and clinical and diagnostic outcome at 2 to 5 years were evaluated by using 2 nationally recognized normative databases: cross-sectional normative data from a national survey and longitudinal data of individual growth. RESULTS Compared with normative data of healthy infants, birth HC in infants with ASD was significantly smaller (z = -0.66, P<.001); after birth, HC increased 1.67 SDs and mean HC was at the 84th percentile by 6 to 14 months. Birth HC was related to cerebellar gray matter volume at 2 to 5 years, although the excessive increase in HC between birth and 6 to 14 months was related to greater cerebral cortex volume at 2 to 5 years. Within the ASD group, every child with autistic disorder had a greater increase in HC between birth and 6 to 14 months (mean [SD], 2.19 [0.98]) than infants with pervasive developmental disorder-not otherwise specified (0.58 [0.35]). Only 6% of the individual healthy infants in the longitudinal data showed accelerated HC growth trajectories (>2.0 SDs) from birth to 6 to 14 months; 59% of infants with autistic disorder showed these accelerated growth trajectories. CONCLUSIONS The clinical onset of autism appears to be preceded by 2 phases of brain growth abnormality: a reduced head size at birth and a sudden and excessive increase in head size between 1 to 2 months and 6 to 14 months. Abnormally accelerated rate of growth may serve as an early warning signal of risk for autism.
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22 |
680 |
3
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May PA, Chambers CD, Kalberg WO, Zellner J, Feldman H, Buckley D, Kopald D, Hasken JM, Xu R, Honerkamp-Smith G, Taras H, Manning MA, Robinson LK, Adam MP, Abdul-Rahman O, Vaux K, Jewett T, Elliott AJ, Kable JA, Akshoomoff N, Falk D, Arroyo JA, Hereld D, Riley EP, Charness ME, Coles CD, Warren KR, Jones KL, Hoyme HE. Prevalence of Fetal Alcohol Spectrum Disorders in 4 US Communities. JAMA 2018; 319:474-482. [PMID: 29411031 PMCID: PMC5839298 DOI: 10.1001/jama.2017.21896] [Citation(s) in RCA: 527] [Impact Index Per Article: 75.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
IMPORTANCE Fetal alcohol spectrum disorders are costly, life-long disabilities. Older data suggested the prevalence of the disorder in the United States was 10 per 1000 children; however, there are few current estimates based on larger, diverse US population samples. OBJECTIVE To estimate the prevalence of fetal alcohol spectrum disorders, including fetal alcohol syndrome, partial fetal alcohol syndrome, and alcohol-related neurodevelopmental disorder, in 4 regions of the United States. DESIGN, SETTING, AND PARTICIPANTS Active case ascertainment methods using a cross-sectional design were used to assess children for fetal alcohol spectrum disorders between 2010 and 2016. Children were systematically assessed in the 4 domains that contribute to the fetal alcohol spectrum disorder continuum: dysmorphic features, physical growth, neurobehavioral development, and prenatal alcohol exposure. The settings were 4 communities in the Rocky Mountain, Midwestern, Southeastern, and Pacific Southwestern regions of the United States. First-grade children and their parents or guardians were enrolled. EXPOSURES Alcohol consumption during pregnancy. MAIN OUTCOMES AND MEASURES Prevalence of fetal alcohol spectrum disorders in the 4 communities was the main outcome. Conservative estimates for the prevalence of the disorder and 95% CIs were calculated using the eligible first-grade population as the denominator. Weighted prevalences and 95% CIs were also estimated, accounting for the sampling schemes and using data restricted to children who received a full evaluation. RESULTS A total of 6639 children were selected for participation from a population of 13 146 first-graders (boys, 51.9%; mean age, 6.7 years [SD, 0.41] and white maternal race, 79.3%). A total of 222 cases of fetal alcohol spectrum disorders were identified. The conservative prevalence estimates for fetal alcohol spectrum disorders ranged from 11.3 (95% CI, 7.8-15.8) to 50.0 (95% CI, 39.9-61.7) per 1000 children. The weighted prevalence estimates for fetal alcohol spectrum disorders ranged from 31.1 (95% CI, 16.1-54.0) to 98.5 (95% CI, 57.5-139.5) per 1000 children. CONCLUSIONS AND RELEVANCE Estimated prevalence of fetal alcohol spectrum disorders among first-graders in 4 US communities ranged from 1.1% to 5.0% using a conservative approach. These findings may represent more accurate US prevalence estimates than previous studies but may not be generalizable to all communities.
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Research Support, N.I.H., Extramural |
7 |
527 |
4
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Michaelson JJ, Shi Y, Gujral M, Zheng H, Malhotra D, Jin X, Jian M, Liu G, Greer D, Bhandari A, Wu W, Corominas R, Peoples A, Koren A, Gore A, Kang S, Lin GN, Estabillo J, Gadomski T, Singh B, Zhang K, Akshoomoff N, Corsello C, McCarroll S, Iakoucheva LM, Li Y, Wang J, Sebat J. Whole-genome sequencing in autism identifies hot spots for de novo germline mutation. Cell 2013; 151:1431-42. [PMID: 23260136 DOI: 10.1016/j.cell.2012.11.019] [Citation(s) in RCA: 397] [Impact Index Per Article: 33.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Revised: 10/05/2012] [Accepted: 10/30/2012] [Indexed: 02/06/2023]
Abstract
De novo mutation plays an important role in autism spectrum disorders (ASDs). Notably, pathogenic copy number variants (CNVs) are characterized by high mutation rates. We hypothesize that hypermutability is a property of ASD genes and may also include nucleotide-substitution hot spots. We investigated global patterns of germline mutation by whole-genome sequencing of monozygotic twins concordant for ASD and their parents. Mutation rates varied widely throughout the genome (by 100-fold) and could be explained by intrinsic characteristics of DNA sequence and chromatin structure. Dense clusters of mutations within individual genomes were attributable to compound mutation or gene conversion. Hypermutability was a characteristic of genes involved in ASD and other diseases. In addition, genes impacted by mutations in this study were associated with ASD in independent exome-sequencing data sets. Our findings suggest that regional hypermutation is a significant factor shaping patterns of genetic variation and disease risk in humans.
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Twin Study |
12 |
397 |
5
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Heaton RK, Akshoomoff N, Tulsky D, Mungas D, Weintraub S, Dikmen S, Beaumont J, Casaletto KB, Conway K, Slotkin J, Gershon R. Reliability and validity of composite scores from the NIH Toolbox Cognition Battery in adults. J Int Neuropsychol Soc 2014; 20:588-98. [PMID: 24960398 PMCID: PMC4103963 DOI: 10.1017/s1355617714000241] [Citation(s) in RCA: 306] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
This study describes psychometric properties of the NIH Toolbox Cognition Battery (NIHTB-CB) Composite Scores in an adult sample. The NIHTB-CB was designed for use in epidemiologic studies and clinical trials for ages 3 to 85. A total of 268 self-described healthy adults were recruited at four university-based sites, using stratified sampling guidelines to target demographic variability for age (20-85 years), gender, education, and ethnicity. The NIHTB-CB contains seven computer-based instruments assessing five cognitive sub-domains: Language, Executive Function, Episodic Memory, Processing Speed, and Working Memory. Participants completed the NIHTB-CB, corresponding gold standard validation measures selected to tap the same cognitive abilities, and sociodemographic questionnaires. Three Composite Scores were derived for both the NIHTB-CB and gold standard batteries: "Crystallized Cognition Composite," "Fluid Cognition Composite," and "Total Cognition Composite" scores. NIHTB Composite Scores showed acceptable internal consistency (Cronbach's alphas=0.84 Crystallized, 0.83 Fluid, 0.77 Total), excellent test-retest reliability (r: 0.86-0.92), strong convergent (r: 0.78-0.90) and discriminant (r: 0.19-0.39) validities versus gold standard composites, and expected age effects (r=0.18 crystallized, r=-0.68 fluid, r=-0.26 total). Significant relationships with self-reported prior school difficulties and current health status, employment, and presence of a disability provided evidence of external validity. The NIH Toolbox Cognition Battery Composite Scores have excellent reliability and validity, suggesting they can be used effectively in epidemiologic and clinical studies.
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Research Support, N.I.H., Extramural |
11 |
306 |
6
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Brown TT, Kuperman JM, Chung Y, Erhart M, McCabe C, Hagler DJ, Venkatraman VK, Akshoomoff N, Amaral DG, Bloss CS, Casey BJ, Chang L, Ernst TM, Frazier JA, Gruen JR, Kaufmann WE, Kenet T, Kennedy DN, Murray SS, Sowell ER, Jernigan TL, Dale AM. Neuroanatomical assessment of biological maturity. Curr Biol 2012; 22:1693-8. [PMID: 22902750 DOI: 10.1016/j.cub.2012.07.002] [Citation(s) in RCA: 254] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Revised: 06/20/2012] [Accepted: 07/02/2012] [Indexed: 11/25/2022]
Abstract
Structural MRI allows unparalleled in vivo study of the anatomy of the developing human brain. For more than two decades, MRI research has revealed many new aspects of this multifaceted maturation process, significantly augmenting scientific knowledge gathered from postmortem studies. Postnatal brain development is notably protracted and involves considerable changes in cerebral cortical, subcortical, and cerebellar structures, as well as significant architectural changes in white matter fiber tracts (see [12]). Although much work has described isolated features of neuroanatomical development, it remains a critical challenge to characterize the multidimensional nature of brain anatomy, capturing different phases of development among individuals. Capitalizing on key advances in multisite, multimodal MRI, and using cross-validated nonlinear modeling, we demonstrate that developmental brain phase can be assessed with much greater precision than has been possible using other biological measures, accounting for more than 92% of the variance in age. Further, our composite metric of morphology, diffusivity, and signal intensity shows that the average difference in phase among children of the same age is only about 1 year, revealing for the first time a latent phenotype in the human brain for which maturation timing is tightly controlled.
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Research Support, N.I.H., Extramural |
13 |
254 |
7
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Jernigan TL, Brown TT, Hagler DJ, Akshoomoff N, Bartsch H, Newman E, Thompson WK, Bloss CS, Murray SS, Schork N, Kennedy DN, Kuperman JM, McCabe C, Chung Y, Libiger O, Maddox M, Casey BJ, Chang L, Ernst TM, Frazier JA, Gruen JR, Sowell ER, Kenet T, Kaufmann WE, Mostofsky S, Amaral DG, Dale AM. The Pediatric Imaging, Neurocognition, and Genetics (PING) Data Repository. Neuroimage 2015; 124:1149-1154. [PMID: 25937488 DOI: 10.1016/j.neuroimage.2015.04.057] [Citation(s) in RCA: 206] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2015] [Revised: 04/26/2015] [Accepted: 04/27/2015] [Indexed: 11/16/2022] Open
Abstract
The main objective of the multi-site Pediatric Imaging, Neurocognition, and Genetics (PING) study was to create a large repository of standardized measurements of behavioral and imaging phenotypes accompanied by whole genome genotyping acquired from typically-developing children varying widely in age (3 to 20 years). This cross-sectional study produced sharable data from 1493 children, and these data have been described in several publications focusing on brain and cognitive development. Researchers may gain access to these data by applying for an account on the PING portal and filing a data use agreement. Here we describe the recruiting and screening of the children and give a brief overview of the assessments performed, the imaging methods applied, the genetic data produced, and the numbers of cases for whom different data types are available. We also cite sources of more detailed information about the methods and data. Finally we describe the procedures for accessing the data and for using the PING data exploration portal.
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Research Support, N.I.H., Extramural |
10 |
206 |
8
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Akshoomoff N, Beaumont JL, Bauer PJ, Dikmen SS, Gershon RC, Mungas D, Slotkin J, Tulsky D, Weintraub S, Zelazo PD, Heaton RK. VIII. NIH Toolbox Cognition Battery (CB): composite scores of crystallized, fluid, and overall cognition. Monogr Soc Res Child Dev 2014; 78:119-32. [PMID: 23952206 DOI: 10.1111/mono.12038] [Citation(s) in RCA: 174] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The NIH Toolbox Cognition Battery (CB) includes 7 tests covering 6 cognitive abilities. This chapter describes the psychometric characteristics in children ages 3-15 years of a total summary score and composite scores reflecting two major types of cognition: "crystallized" (more dependent upon past learning experiences) and "fluid" (capacity for new learning and information processing in novel situations). Both types of cognition are considered important in everyday functioning, but are thought to be differently affected by brain health status throughout life, from early childhood through older adulthood. All three Toolbox composite scores showed excellent test-retest reliability, robust developmental effects across the childhood age range considered here, and strong correlations with established measures of similar abilities. Additional preliminary evidence of validity includes significant associations between all three Toolbox composite scores and maternal reports of children's health status and school performance.
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Journal Article |
11 |
174 |
9
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Akshoomoff N, Newman E, Thompson WK, McCabe C, Bloss CS, Chang L, Amaral DG, Casey BJ, Ernst TM, Frazier JA, Gruen JR, Kaufmann WE, Kenet T, Kennedy DN, Libiger O, Mostofsky S, Murray SS, Sowell ER, Schork N, Dale AM, Jernigan TL. The NIH Toolbox Cognition Battery: results from a large normative developmental sample (PING). Neuropsychology 2014; 28:1-10. [PMID: 24219608 PMCID: PMC3925365 DOI: 10.1037/neu0000001] [Citation(s) in RCA: 139] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
OBJECTIVE The NIH Toolbox Cognition Battery (NTCB) was designed to provide a brief, efficient computerized test of key neuropsychological functions appropriate for use in children as young as 3 years of age. This report describes the performance of a large group of typically developing children and adolescents and examines the impact of age and sociocultural variables on test performance. METHOD The NTCB was administered to a sample of 1,020 typically developing males and females ranging in age from 3 to 20 years, diverse in terms of socioeconomic status (SES) and race/ethnicity, as part of the new publicly accessible Pediatric Imaging, Neurocognition, and Genetics (PING) data resource, at 9 sites across the United States. RESULTS General additive models of nonlinear age-functions were estimated from age-differences in test performance on the 8 NTCB subtests while controlling for family SES and genetic ancestry factors (GAFs). Age accounted for the majority of the variance across all NTCB scores, with additional significant contributions of gender on some measures, and of SES and race/ethnicity (GAFs) on all. After adjusting for age and gender, SES and GAFs explained a substantial proportion of the remaining unexplained variance in Picture Vocabulary scores. CONCLUSIONS The results highlight the sensitivity to developmental effects and efficiency of this new computerized assessment battery for neurodevelopmental research. Limitations are observed in the form of some ceiling effects in older children, some floor effects, particularly on executive function tests in the youngest participants, and evidence for variable measurement sensitivity to cultural/socioeconomic factors.
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Research Support, N.I.H., Extramural |
11 |
139 |
10
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Akshoomoff N. Use of the Mullen Scales of Early Learning for the assessment of young children with Autism Spectrum Disorders. Child Neuropsychol 2006; 12:269-77. [PMID: 16911972 PMCID: PMC1550495 DOI: 10.1080/09297040500473714] [Citation(s) in RCA: 122] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The psychological assessment is an important component of the diagnostic evaluation in young children suspected of having an Autism Spectrum Disorder but can be hampered by behavioral difficulties. Overt behaviors during administration of the Mullen Scales of Early Learning were coded in 22 preschoolers with an Autism Spectrum Disorder and 20 age-matched typically developing children. Children in the Autism Spectrum Disorder group required less time to complete the assessment but spent proportionally more time exhibiting off-task behaviors and less time engaged with the assessment. Scores obtained on the Mullen Scales were positively correlated with level of engagement and negatively correlated with off task behaviors.
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Research Support, U.S. Gov't, Non-P.H.S. |
19 |
122 |
11
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Kim SJ, Cox N, Courchesne R, Lord C, Corsello C, Akshoomoff N, Guter S, Leventhal BL, Courchesne E, Cook EH. Transmission disequilibrium mapping at the serotonin transporter gene (SLC6A4) region in autistic disorder. Mol Psychiatry 2002; 7:278-88. [PMID: 11920155 DOI: 10.1038/sj.mp.4001033] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2001] [Revised: 09/09/2001] [Accepted: 11/14/2001] [Indexed: 11/09/2022]
Abstract
The serotonin transporter gene (SLC6A4, MIM 182138) is a candidate gene in autistic disorder based on neurochemical, neuroendocrine studies and the efficacy of potent serotonin transporter inhibitors in reducing ritualistic behaviors and related aggression. An insertion/deletion polymorphism (5-HTTLPR) in the promoter region and a variable number of tandem repeat polymorphism (VNTR) in the second intron, were previously identified and suggested to modulate transcription. Six previous family-based association studies of SLC6A4 in autistic disorder have been conducted, with four studies showing nominally significant transmission disequilibrium and two studies with no evidence of nominally significant transmission disequilibrium. In the present study, TDT was conducted in 81 new trios. A previous finding of transmission disequilibrium between a haplotype consisting of the 5-HTTLPR and intron 2 VNTR was replicated in this study, but not preferential transmission of 5-HTTLPR as an independent marker. Because of inconsistent transmission of 5-HTTLPR across studies, SLC6A4 and its flanking regions were sequenced in 10 probands, followed by typing of 20 single nucleotide polymorphisms (SNPs) and seven simple sequence repeat (SSR) polymorphisms in 115 autism trios. When individual markers were analyzed by TDT, seven SNP markers and four SSR markers (six SNPs, 5-HTTLPR and the second intron VNTR from promoter 1A through intron 2 of SLC6A4, one SSR from intron 7 of SLC6A4, one SNP from the bleomycin hydrolase gene (BLMH, MIM 602403) and one SSR telomeric to BLMH) showed nominally significant evidence of transmission disequilibrium. Four markers showed stronger evidence of transmission disequilibrium (TDT(max) P = 0.0005) than 5-HTTLPR.
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23 |
104 |
12
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Akshoomoff N, Lord C, Lincoln AJ, Courchesne RY, Carper RA, Townsend J, Courchesne E. Outcome classification of preschool children with autism spectrum disorders using MRI brain measures. J Am Acad Child Adolesc Psychiatry 2004; 43:349-57. [PMID: 15076269 DOI: 10.1097/00004583-200403000-00018] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To test the hypothesis that a combination of magnetic resonance imaging (MRI) brain measures obtained during early childhood distinguish children with autism spectrum disorders (ASD) from typically developing children and is associated with functional outcome. METHOD Quantitative MRI technology was used to measure gray and white matter volumes (cerebrum and cerebellum), total brain volume, and the area of the cerebellar vermis in 52 boys with a provisional diagnosis of autism (aged 1.9-5.2 years) and 15 typically developing young children (aged 1.7-5.2 years). Diagnostic confirmation and cognitive outcome data were obtained after the children reached 5 years of age. RESULTS A discriminant function analysis of the MRI brain measures correctly classified 95.8% of the ASD cases and 92.3% of the control cases. This set of variables also correctly classified 85% of the ASD cases as lower functioning and 68% of the ASD cases as higher functioning. CONCLUSIONS These results indicate that variability in cerebellar and cerebral size is correlated with diagnostic and functional outcome in very young children with ASD.
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21 |
103 |
13
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McCleery JP, Akshoomoff N, Dobkins KR, Carver LJ. Atypical face versus object processing and hemispheric asymmetries in 10-month-old infants at risk for autism. Biol Psychiatry 2009; 66:950-7. [PMID: 19765688 PMCID: PMC2783702 DOI: 10.1016/j.biopsych.2009.07.031] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2009] [Revised: 07/20/2009] [Accepted: 07/22/2009] [Indexed: 12/13/2022]
Abstract
BACKGROUND Previous studies have documented atypicalities in face/object processing in children and adults with autism spectrum disorders (ASDs). To investigate whether such atypicalities may reflect a genetically mediated risk factor present early in development, we measured face/object processing in 10-month-old high-risk infants who carry some of the genes associated with ASD because they have an older sibling diagnosed with the disorder. METHODS We employed event-related potentials (ERPs) to measure cortical responses to pictures of faces and objects, the objects being toys. Latencies and amplitudes of four ERP components (P100, N290, P400, and Nc) were compared between 20 high-risk infants and 20 low-risk control subjects (infants with no family history of ASD). RESULTS Responses to faces versus objects differed between high- and low-risk infants for the latencies of the N290 and P400. Differences were driven by faster responses to faces than objects in low-risk, but not high-risk, infants (P400) and, conversely, faster responses to objects than faces in high-risk, but not low-risk, infants (N290). Object responses were also faster in high-risk than low-risk infants (both N290 and P400). Left versus right hemisphere responses also differed between high- and low-risk infants for the amplitudes of the P100, N290, and P400; collapsed across faces/objects, low-risk, but not high-risk, infants exhibited hemisphere asymmetries. CONCLUSIONS Genetic risk for ASD is associated with atypical face versus object processing and an atypical lack of hemispheric asymmetry early in life. These atypicalities might contribute to development of the disorder.
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research-article |
16 |
100 |
14
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Akshoomoff N, Pierce K, Courchesne E. The neurobiological basis of autism from a developmental perspective. Dev Psychopathol 2003; 14:613-34. [PMID: 12349876 DOI: 10.1017/s0954579402003115] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Autism is a neurobiological disorder that is diagnosed through careful behavioral assessment in early childhood. In this paper, we review recent studies that have attempted to reveal the underlying causes of autism using a variety of techniques. Particular emphasis is placed on techniques that have been used by a number of different laboratories, including structural magnetic resonance imaging and postmortem studies of neuroanatomy. Neurobiological and neuropsychological data from individuals across a wide age range are examined from a neurodevelopmental perspective. We discuss how these recent advances have led us to develop a growth dysregulation hypothesis of autism. Finally, we discuss how this hypothesis may lead to new innovations in autism research.
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Review |
22 |
95 |
15
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Kleinhans N, Akshoomoff N, Delis DC. Executive Functions in Autism and Asperger's Disorder: Flexibility, Fluency, and Inhibition. Dev Neuropsychol 2005; 27:379-401. [PMID: 15843103 DOI: 10.1207/s15326942dn2703_5] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
The Color-Word Interference Test, Trail Making Test, Verbal Fluency Test, and Design Fluency Test from the Delis-Kaplan Executive Function System (Delis, Kaplan, & Kramer, 2001) were administered to 12 high-functioning adults and adolescents with autistic disorder or Asperger's disorder. Each test included a switching condition in addition to baseline and/or other executive-function conditions. Participants performed significantly below average on a composite measure of executive functioning adjusted for baseline cognitive ability. Complex verbal tasks that required cognitive switching and initiation of efficient lexical retrieval strategies produced the most consistent deficits, whereas cognitive inhibition was intact. We discuss implications of these findings for understanding the neurocognitive substrates of autistic spectrum disorders.
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20 |
90 |
16
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Gaffrey MS, Kleinhans NM, Haist F, Akshoomoff N, Campbell A, Courchesne E, Müller RA. Atypical [corrected] participation of visual cortex during word processing in autism: an fMRI study of semantic decision. Neuropsychologia 2007; 45:1672-84. [PMID: 17336346 PMCID: PMC2071933 DOI: 10.1016/j.neuropsychologia.2007.01.008] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2006] [Revised: 12/26/2006] [Accepted: 01/07/2007] [Indexed: 11/22/2022]
Abstract
Language delay and impairment are salient features of autism. More specifically, there is evidence of atypical semantic organization in autism, but the functional brain correlates are not well understood. The current study used functional MRI to examine activation associated with semantic category decision. Ten high-functioning men with autism spectrum disorder and 10 healthy control subjects matched for gender, handedness, age, and nonverbal IQ were studied. Participants indicated via button press response whether visually presented words belonged to a target category (tools, colors, feelings). The control condition required target letter detection in unpronounceable letter strings. Significant activation for semantic decision in the left inferior frontal gyrus (Brodmann areas 44 and 45) was found in the control group. Corresponding activation in the autism group was more limited, with smaller clusters in left inferior frontal areas 45 and 47. Autistic participants, however, showed significantly greater activation compared to controls in extrastriate visual cortex bilaterally (areas 18 and 19), which correlated with greater number of errors on the semantic task. Our findings suggest an important role of perceptual components (possibly visual imagery) during semantic decision, consistent with previous evidence of atypical lexicosemantic performance in autism. In the context of similar findings from younger typically developing children, our results suggest an immature pattern associated with inefficient processing, presumably due to atypical experiential embedding of word acquisition in autism.
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Research Support, N.I.H., Extramural |
18 |
87 |
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Eicher JD, Powers NR, Miller LL, Akshoomoff N, Amaral DG, Bloss CS, Libiger O, Schork NJ, Darst BF, Casey BJ, Chang L, Ernst T, Frazier J, Kaufmann WE, Keating B, Kenet T, Kennedy D, Mostofsky S, Murray SS, Sowell ER, Bartsch H, Kuperman JM, Brown TT, Hagler DJ, Dale AM, Jernigan TL, St Pourcain B, Davey Smith G, Ring SM, Gruen JR. Genome-wide association study of shared components of reading disability and language impairment. GENES, BRAIN, AND BEHAVIOR 2013; 12:792-801. [PMID: 24024963 PMCID: PMC3904347 DOI: 10.1111/gbb.12085] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Revised: 08/16/2013] [Accepted: 09/09/2013] [Indexed: 11/29/2022]
Abstract
Written and verbal languages are neurobehavioral traits vital to the development of communication skills. Unfortunately, disorders involving these traits-specifically reading disability (RD) and language impairment (LI)-are common and prevent affected individuals from developing adequate communication skills, leaving them at risk for adverse academic, socioeconomic and psychiatric outcomes. Both RD and LI are complex traits that frequently co-occur, leading us to hypothesize that these disorders share genetic etiologies. To test this, we performed a genome-wide association study on individuals affected with both RD and LI in the Avon Longitudinal Study of Parents and Children. The strongest associations were seen with markers in ZNF385D (OR = 1.81, P = 5.45 × 10(-7) ) and COL4A2 (OR = 1.71, P = 7.59 × 10(-7) ). Markers within NDST4 showed the strongest associations with LI individually (OR = 1.827, P = 1.40 × 10(-7) ). We replicated association of ZNF385D using receptive vocabulary measures in the Pediatric Imaging Neurocognitive Genetics study (P = 0.00245). We then used diffusion tensor imaging fiber tract volume data on 16 fiber tracts to examine the implications of replicated markers. ZNF385D was a predictor of overall fiber tract volumes in both hemispheres, as well as global brain volume. Here, we present evidence for ZNF385D as a candidate gene for RD and LI. The implication of transcription factor ZNF385D in RD and LI underscores the importance of transcriptional regulation in the development of higher order neurocognitive traits. Further study is necessary to discern target genes of ZNF385D and how it functions within neural development of fluent language.
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Research Support, N.I.H., Extramural |
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79 |
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Brandler WM, Antaki D, Gujral M, Noor A, Rosanio G, Chapman TR, Barrera DJ, Lin GN, Malhotra D, Watts AC, Wong LC, Estabillo JA, Gadomski TE, Hong O, Fajardo KVF, Bhandari A, Owen R, Baughn M, Yuan J, Solomon T, Moyzis AG, Maile MS, Sanders SJ, Reiner GE, Vaux KK, Strom CM, Zhang K, Muotri AR, Akshoomoff N, Leal SM, Pierce K, Courchesne E, Iakoucheva LM, Corsello C, Sebat J. Frequency and Complexity of De Novo Structural Mutation in Autism. Am J Hum Genet 2016; 98:667-79. [PMID: 27018473 PMCID: PMC4833290 DOI: 10.1016/j.ajhg.2016.02.018] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 02/18/2016] [Indexed: 12/22/2022] Open
Abstract
Genetic studies of autism spectrum disorder (ASD) have established that de novo duplications and deletions contribute to risk. However, ascertainment of structural variants (SVs) has been restricted by the coarse resolution of current approaches. By applying a custom pipeline for SV discovery, genotyping, and de novo assembly to genome sequencing of 235 subjects (71 affected individuals, 26 healthy siblings, and their parents), we compiled an atlas of 29,719 SV loci (5,213/genome), comprising 11 different classes. We found a high diversity of de novo mutations, the majority of which were undetectable by previous methods. In addition, we observed complex mutation clusters where combinations of de novo SVs, nucleotide substitutions, and indels occurred as a single event. We estimate a high rate of structural mutation in humans (20%) and propose that genetic risk for ASD is attributable to an elevated frequency of gene-disrupting de novo SVs, but not an elevated rate of genome rearrangement.
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Research Support, N.I.H., Extramural |
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66 |
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Lazenby DC, Sideridis GD, Huntington N, Prante M, Dale PS, Curtin S, Henkel L, Iverson JM, Carver L, Dobkins K, Akshoomoff N, Tagavi D, Nelson CA, Tager-Flusberg H. Language Differences at 12 Months in Infants Who Develop Autism Spectrum Disorder. J Autism Dev Disord 2016; 46:899-909. [PMID: 26476738 DOI: 10.1007/s10803-015-2632-1] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Little is known about early language development in infants who later develop autism spectrum disorder (ASD). We analyzed prospective data from 346 infants, some of whom were at high risk for developing ASD, to determine if language differences could be detected at 12 months of age in the infants who later were diagnosed with ASD. Analyses revealed lower receptive and expressive language scores in infants who later were diagnosed with ASD. Controlling for overall ability to understand and produce single words, a Rasch analysis indicated that infants who later developed ASD had a higher degree of statistically unexpected word understanding and production. At 12 months of age, quantitative and qualitative language patterns distinguished infants who later developed ASD from those who did not.
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Research Support, U.S. Gov't, P.H.S. |
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Grillon C, Courchesne E, Akshoomoff N. Brainstem and middle latency auditory evoked potentials in autism and developmental language disorder. J Autism Dev Disord 1989; 19:255-69. [PMID: 2745391 DOI: 10.1007/bf02211845] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Brainstem auditory evoked potentials (BAEP) and middle latency responses (MLR) were studied in 8 nonretarded subjects with infantile autism (mean age = 23.3, SD = 2.8), 8 subjects with receptive developmental language disorder (mean age = 16.3, SD = 1.4), and normal control subjects matched to each group for age, gender, and Performance IQ. Click stimuli were delivered monaurally to the left and the right ear and binaurally for both the BAEPs (70-dB HL, 7/sec) and the MLRs (60-dB HL, 13/sec). Amplitudes and latencies (Waves I to VI), interwave latencies (III-V, I-V, and I-III), and Wave I/V amplitude ratio of the BAEPs were determined for each group. For the MLR study, Wave Na, Pa, and Nb latencies, and Wave Na-Pa and Pa-Nb amplitudes were calculated. There were no consistent differences in the BAEP and MLR characteristics of the control and the experimental groups. These results suggest that the abnormal cognitive processes indexed by the cognitive and attention-related event-related potential components in infantile autism and receptive developmental language disorder are not due to abnormal sensory processing in the brainstem and in areas central to the brainstem whose activity generates the BAEPs and MLRs.
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Katheria A, Garey D, Truong G, Akshoomoff N, Steen J, Maldonado M, Poeltler D, Harbert MJ, Vaucher YE, Finer N. A Randomized Clinical Trial of Umbilical Cord Milking vs Delayed Cord Clamping in Preterm Infants: Neurodevelopmental Outcomes at 22-26 Months of Corrected Age. J Pediatr 2018; 194:76-80. [PMID: 29246467 PMCID: PMC9442450 DOI: 10.1016/j.jpeds.2017.10.037] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 10/04/2017] [Accepted: 10/13/2017] [Indexed: 12/24/2022]
Abstract
OBJECTIVE To compare the effect of umbilical cord milking vs delayed cord clamping (DCC) on neurodevelopmental and health outcomes in very preterm infants at 22-26 months of corrected age. STUDY DESIGN Neurodevelopmental outcomes at 2 years of age were assessed using the Bayley Scales of Infant Development, third edition, and a standardized neurologic examination. Data regarding pulmonary morbidities, neurosensory impairments, and hospitalizations were obtained by parental interview. Intention-to-treat was used for primary analyses. RESULTS Of the 197 infants enrolled in the original study there were 15 deaths, 5 in the umbilical cord milking group and 10 in DCC group. Of the remaining infants, 135 (74%) were assessed at 22-26 months of corrected age. Demographics in umbilical cord milking (n = 70) and DCC (n = 65) groups were similar. Infants randomized to umbilical cord milking at birth had significantly higher cognitive and language composite scores, and were less likely to have a cognitive composite score of <85 (4% vs 15%; P = .04). Motor function was similar in both groups. There were no differences in the incidences of mild or moderate to severe neurodevelopmental impairment, hearing or visual impairments, pulmonary morbidities, or rehospitalizations between the 2 groups. CONCLUSIONS Infants randomized to umbilical cord milking had higher language and cognitive scores compared with those randomized to DCC. There was no difference in rates of mild or moderate to severe neurodevelopmental impairment. TRIAL REGISTRATION clinicaltrials.gov: NCT01434732.
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Casaletto KB, Umlauf A, Marquine M, Beaumont JL, Mungas D, Gershon R, Slotkin J, Akshoomoff N, Heaton RK. Demographically Corrected Normative Standards for the Spanish Language Version of the NIH Toolbox Cognition Battery. J Int Neuropsychol Soc 2016; 22:364-74. [PMID: 26817924 PMCID: PMC5107311 DOI: 10.1017/s135561771500137x] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Hispanics are the fastest growing ethnicity in the United States, yet there are limited well-validated neuropsychological tools in Spanish, and an even greater paucity of normative standards representing this population. The Spanish NIH Toolbox Cognition Battery (NIHTB-CB) is a novel neurocognitive screener; however, the original norms were developed combining Spanish- and English-versions of the battery. We developed normative standards for the Spanish NIHTB-CB, fully adjusting for demographic variables and based entirely on a Spanish-speaking sample. A total of 408 Spanish-speaking neurologically healthy adults (ages 18-85 years) and 496 children (ages 3-7 years) completed the NIH Toolbox norming project. We developed three types of scores: uncorrected based on the entire Spanish-speaking cohort, age-corrected, and fully demographically corrected (age, education, sex) scores for each of the seven NIHTB-CB tests and three composites (Fluid, Crystallized, Total Composites). Corrected scores were developed using polynomial regression models. Demographic factors demonstrated medium-to-large effects on uncorrected NIHTB-CB scores in a pattern that differed from that observed on the English NIHTB-CB. For example, in Spanish-speaking adults, education was more strongly associated with Fluid scores, but showed the strongest association with Crystallized scores among English-speaking adults. Demographic factors were no longer associated with fully corrected scores. The original norms were not successful in eliminating demographic effects, overestimating children's performances, and underestimating adults' performances on the Spanish NIHTB-CB. The disparate pattern of demographic associations on the Spanish versus English NIHTB-CB supports the need for distinct normative standards developed separately for each population. Fully adjusted scores presented here will aid in more accurately characterizing acquired brain dysfunction among U.S. Spanish-speakers.
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Research Support, N.I.H., Extramural |
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Favier R, Akshoomoff N, Mattson S, Grossfeld P. Jacobsen syndrome: Advances in our knowledge of phenotype and genotype. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2015; 169:239-50. [PMID: 26285164 DOI: 10.1002/ajmg.c.31448] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In 1973, the Danish geneticist Petrea Jacobsen described a three-generation family in which the proband carried a presumed terminal deletion at the end of the long arm of chromosome 11 (11q). This patient had dysmorphic features, congenital heart disease, and intellectual disability. Since Dr. Jacobsen's initial report, over 200 patients with Jacobsen syndrome have been reported, suggesting that Jacobsen syndrome is a contiguous gene disorder. With the advent of high resolution deletion mapping and the completion of the human genome sequencing project, a comprehensive genotype/phenotype analysis for Jacobsen syndrome became possible. In this article, we review research describing individual causal genes in distal 11q that contribute to the overall Jacobsen syndrome clinical phenotype. Through a combination of human genetics and the use of genetically engineered animal models, causal genes have been identified for the clinical problems in JS that historically have caused the greatest morbidity and mortality: congenital heart disease, the Paris-Trousseau bleeding disorder, intellectual disability, autism, and immunodeficiency. Insights gained from these studies are being applied for future drug development and clinical trials, as well as for a potential strategy for the prevention of certain forms of congenital heart disease. The results of these studies will likely not only improve the prognostic and therapeutic approaches for patients with Jacobsen syndrome, but also for the general population afflicted with these problems.
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Review |
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Corsello CM, Akshoomoff N, Stahmer AC. Diagnosis of autism spectrum disorders in 2-year-olds: a study of community practice. J Child Psychol Psychiatry 2013; 54:178-85. [PMID: 22905987 PMCID: PMC3505251 DOI: 10.1111/j.1469-7610.2012.02607.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Longitudinal research studies have demonstrated that experienced clinicians using standardized assessment measures can make a reliable diagnosis of autism spectrum disorders (ASDs) in children under age 3. Limited data are available regarding the sensitivity and specificity of these measures in community settings. The aims of this study were to determine how well a standardized diagnostic observational measure (Autism Diagnostic Observation Schedule - ADOS) functions alone, and with a brief parent measure within a community setting when administered by community clinicians. METHODS Clinical records for 138 children between the ages of 24 and 36 months of age who were evaluated for possible ASD or social/language concerns at a hospital-based developmental evaluation clinic were examined. Evaluations were conducted by community-based clinical psychologists. Classification results obtained from standardized diagnostic measures were compared with case reviewer diagnosis, by reviewers blind to scores on diagnostic measures, using The Records-based Methodology for ASD Case Definition that was developed by the Metropolitan Atlanta Developmental Disabilities Surveillance Program. RESULTS When compared with case review diagnosis, the ADOS demonstrated strong sensitivity and specificity for both Autism versus Not Autism and ASD versus Nonspectrum (NS) diagnoses in this young sample. The Social Communication Questionnaire (SCQ), using the lower cutoff of ≥12, had adequate sensitivity when differentiating Autism from Not Autism, but weak sensitivity when differentiating ASD from NS, missing about 80% of the children with pervasive developmental disorder - not otherwise specified. Using either the Modified Checklist for Autism in Toddlers or the SCQ in combination with the ADOS did not result in improved specificity over the ADOS alone and led to a drop in sensitivity when differentiating ASD from NS disorders. CONCLUSIONS These results demonstrate that following best practice guidelines, the ADOS can be successfully incorporated into clinical practice with relatively good sensitivity and specificity, and worked well with a referred sample of 2-year-olds. A parent questionnaire did not lead to any improvement in diagnostic classification above the ADOS used in isolation.
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Chang L, Douet V, Bloss C, Lee K, Pritchett A, Jernigan TL, Akshoomoff N, Murray SS, Frazier J, Kennedy DN, Amaral DG, Gruen J, Kaufmann WE, Casey BJ, Sowell E, Ernst T. Gray matter maturation and cognition in children with different APOE ε genotypes. Neurology 2016; 87:585-94. [PMID: 27412137 DOI: 10.1212/wnl.0000000000002939] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 03/28/2016] [Indexed: 01/15/2023] Open
Abstract
OBJECTIVE The aims of the current study were to determine whether children with the 6 different APOE ε genotypes show differences in gray matter maturation, particularly for those with ε4 and ε2 alleles, which are associated with poorer outcomes in many neurologic disorders. METHODS A total of 1,187 healthy children (aged 3-20 years, 52.1% boys, 47.9% girls) with acceptable data from the cross-sectional Pediatric Imaging Neurocognition and Genetics Study were evaluated for the effects of 6 APOE ε genotypes on macroscopic and microscopic cortical and subcortical gray matter structures (measured with 3-tesla MRI and FreeSurfer for automated morphometry) and on cognition (NIH Toolbox). RESULTS Among APOE ε4 carriers, age-related changes in brain structures and cognition varied depending on genotype, with the smallest hippocampi in ε2ε4 children, the lowest hippocampal fractional anisotropy in younger ε4ε4 children, the largest medial orbitofrontal cortical areas in ε3ε4 children, and age-dependent thinning of the entorhinal cortex in ε4ε4 children. Younger ε4ε4 children had the lowest scores on executive function and working memory, while younger ε2ε4 children performed worse on attention tasks. Larger parietal gyri in the younger ε2ε4 children, and thinner temporal and cingulate isthmus cortices or smaller hippocampi in the younger ε4ε4 children, predicted poorer performance on attention or working memory. CONCLUSIONS Our findings validated and extended prior smaller studies that showed altered brain development in APOE ε4-carrier children. The ε4ε4 and ε2ε4 genotypes may negatively influence brain development and brain aging at the extremes of age. Studying APOE ε polymorphisms in young children may provide the earliest indicators for individuals who might benefit from early interventions or preventive measures for future brain injuries and dementia.
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Journal Article |
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