1. Bahi-Buisson N, Nectoux J, Girard B, Van Esch H, De Ravel T, Boddaert N, Plouin P, Rio M, Fichou Y, Chelly J, Bienvenu T. {{Revisiting the phenotype associated with FOXG1 mutations: two novel cases of congenital Rett variant}}. {Neurogenetics};2009 (Oct 6)
The Forkhead box G1 (FOXG1) is a transcription factor that is critical for forebrain development, where it promotes progenitor proliferation and suppresses premature neurogenesis. Recently, the FOXG1 gene was implicated in the molecular aetiology of the congenital variant of Rett syndrome. So far, 15 FOXG1 molecular alterations, including only eight point mutations, have been reported. We screened the FOXG1 gene in a cohort of 206 MECP2 and CDKL5 mutation negative patients (136 females and 70 males) with severe encephalopathy and microcephaly. The screening was negative in all males, but two de novo mutations (c.1248C>G, p.Y416X and c.460_461dupG, p.E154GfsX300) were identified in two unrelated girls. Both patients showed neurological symptoms from the neonatal period with poor reactivity, hypotonia, and severe microcephaly. During the first year of life, both patients had feeding difficulties and made slow developmental progress. At 5 years old, the girls were significantly neurologically impaired with gross hypotonia, no language, convergent strabismus, and no voluntary hand use. Moreover, they presented a combination of jerky movements, hand-mouthing, and hand-washing stereotypies. Hence, FOXG1 mutation patients demonstrate severe encephalopathy compatible with the congenital variant, as well as additional features such as absent eye contact, inconsolable crying during the perinatal period, and delayed myelination with thin to hypoplastic corpus callosum. Although the overall frequency of mutations in FOXG1 in females with severe mental retardation and microcephaly appears to be low (1.5%), our findings suggest the requirement to investigate both point mutations and gene dosage in the FOXG1 gene in patients with severe encephalopathy with microcephaly and some Rett-like features.
2. Kogan MD, Blumberg SJ, Schieve LA, Boyle CA, Perrin JM, Ghandour RM, Singh GK, Strickland BB, Trevathan E, van Dyck PC. {{Prevalence of Parent-Reported Diagnosis of Autism Spectrum Disorder Among Children in the US, 2007}}. {Pediatrics};2009 (Oct 5)
Objectives: The reported increasing prevalence of autism spectrum disorder (ASD) and attendant health and family impact make monitoring of ASD prevalence a public health priority. Methods: The prevalence of parent-reported diagnosis of ASD among US children aged 3 to 17 years was estimated from the 2007 National Survey of Children’s Health (sample size: 78037). A child was considered to have ASD if a parent/guardian reported that a doctor or other health care provider had ever said that the child had ASD and that the child currently had the condition. The point-prevalence for ASD was calculated for those children meeting both criteria. We examined sociodemographic factors associated with current ASD and with a past (but not current) ASD diagnosis. The health care experiences for children in both ASD groups were explored. Results: The weighted current ASD point-prevalence was 110 per 10,000. We estimate that 673,000 US children have ASD. Odds of having ASD were 4 times as large for boys than girls. Non-Hispanic (NH) black and multiracial children had lower odds of ASD than NH white children. Nearly 40% of those ever diagnosed with ASD did not currently have the condition; NH black children were more likely than NH white children to not have current ASD. Children in both ASD groups were less likely than children without ASD to receive care within a medical home. Conclusions: The observed point-prevalence is higher than previous US estimates. More inclusive survey questions, increased population awareness, and improved screening and identification by providers may partly explain this finding.
3. Rosenberg RE, Law JK, Yenokyan G, McGready J, Kaufmann WE, Law PA. {{Characteristics and concordance of autism spectrum disorders among 277 twin pairs}}. {Arch Pediatr Adolesc Med};2009 (Oct);163(10):907-914.
OBJECTIVES: To examine patterns of autism spectrum disorder (ASD) inheritance and other features in twin pairs by zygosity, sex, and specific ASD diagnosis. DESIGN: Cross-sectional study. SETTING: Internet-based autism registry for US residents. PARTICIPANTS: Survey results from 277 twin pairs (210 dizygotic [DZ] and 67 monozygotic [MZ]) aged 18 years or younger with at least 1 affected twin. MAIN EXPOSURES: Zygosity and sex. OUTCOME MEASURES: Concordance within twin pairs of diagnosis, natural history, and results from standardized autism screening. RESULTS: Pairwise ASD concordance was 31% for DZ and 88% for MZ twins. Female and male MZ twins were 100% and 86% concordant, respectively, and DZ twin pairs with at least 1 female were less likely to be concordant (20%) than were male-male DZ twin pairs (40%). The hazard ratio for ASD diagnosis of the second twin after a first-twin diagnosis was 7.48 for MZ vs DZ twins (95% confidence interval, 3.8-14.7). Affected DZ individual twins had an earlier age at first parental concern and more frequent diagnoses of intellectual disability than did MZ twins; MZ twins had a higher prevalence of bipolar disorder and Asperger syndrome and higher concordance of the latter. Results of autism screening correlated with parent-reported ASD status in more than 90% of cases. CONCLUSIONS: Our data support greater ASD concordance in MZ vs DZ twins. Overall higher functioning, psychiatric comorbidity, and Asperger syndrome concordance among affected MZ vs DZ twins may also suggest differential heritability for different ASDs. For families in which one MZ twin is diagnosed with ASD, the second twin is unlikely to receive an ASD diagnosis after 12 months. In addition, Internet parent report of ASD status is valid.
4. Rosenberg RE, Mandell DS, Farmer JE, Law JK, Marvin AR, Law PA. Psychotropic {{Medication Use Among Children With Autism Spectrum Disorders Enrolled in a National Registry, 2007-2008}}. {J Autism Dev Disord};2009 (Oct 6)
Patterns of current psychotropic medication use among 5,181 children with autism spectrum disorders (ASD) enrolled in a Web-based registry were examined. Overall, 35% used at least one psychotropic medication, most commonly stimulants, neuroleptics, and/or antidepressants. Those who were uninsured or exclusively privately insured were less likely to use >/=3 medications than were those insured by Medicaid. Psychiatrists and neurologists prescribed the majority of psychotropic medications. In multivariate analysis, older age, presence of intellectual disability or psychiatric comorbidity, and residing in a poorer county or in the South or Midwest regions of the United States increased the odds of psychotropic medication use. Factors external to clinical presentation likely affect odds of psychotropic medication use among children with ASD.