1. Ka M, Kim WY. {{ANKRD11 associated with intellectual disability and autism regulates dendrite differentiation via the BDNF/TrkB signaling pathway}}. {Neurobiol Dis};2017 (Dec 21)
Haploinsufficiency of ANKRD11 due to deletion or truncation mutations causes KBG syndrome, a rare genetic disorder characterized by intellectual disability, autism spectrum disorder, and craniofacial abnormalities. However, little is known about the neurobiological role of ANKRD11 during brain development. Here we show that ANKRD11 regulates pyramidal neuron migration and dendritic differentiation in the developing moue cerebral cortex. Using an in utero manipulation approach, we found that Ankrd11 knockdown delayed radial migration of cortical neurons. ANKRD11-deficient neurons displayed markedly reduced dendrite growth and branching as well as abnormal dendritic spine morphology. Ankrd11 knockdown suppressed acetylation of epigenetic molecules such as p53 and Histone H3. Furthermore, the mRNA levels of Trkb, Bdnf, and neurite growth-related genes were downregulated in ANKRD11-deficient cortical neurons. The Trkb promoter region was largely devoid of acetylated Histone H3 and p53, and was instead occupied with MeCP2 and DNMT1. Overexpression of TrkB rescued abnormal dendrite growth in these cells. Our findings demonstrate a novel role for ANKRD11 in neuron differentiation during brain development and suggest an epigenetic modification as a potential key molecular feature underlying KBG syndrome.
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2. Kang DW, Ilhan ZE, Isern NG, Hoyt DW, Howsmon DP, Shaffer M, Lozupone CA, Hahn J, Adams JB, Krajmalnik-Brown R. {{Differences in fecal microbial metabolites and microbiota of children with autism spectrum disorders}}. {Anaerobe};2017 (Dec 21)
Evidence supporting that gut problems are linked to ASD symptoms has been accumulating both in humans and animal models of ASD. Gut microbes and their metabolites may be linked not only to GI problems but also to ASD behavior symptoms. Despite this high interest, most previous studies have looked mainly at microbial structure, and studies on fecal metabolites are rare in the context of ASD. Thus, we aimed to detect fecal metabolites that may be present at significantly different concentrations between 21 children with ASD and 23 neurotypical children and to investigate its possible link to human gut microbiome. Using NMR spectroscopy and 16S rRNA gene amplicon sequencing, we examined metabolite profiles and microbial compositions in fecal samples, respectively. Of the 59 metabolites detected, isopropanol concentrations were significantly higher in feces of children with ASD after multiple testing corrections. We also observed similar trends of fecal metabolites to previous studies; children with ASD have higher fecal p-cresol and possibly lower GABA concentrations. In addition, Fisher Discriminant Analysis (FDA) with leave-out-validation suggested that a group of metabolites-caprate, nicotinate, glutamine, thymine, and aspartate-may potentially function as a modest biomarker to separate ASD participants from the neurotypical group (78% sensitivity and 81% specificity). Consistent with our previous Arizona cohort study, we also confirmed lower gut microbial diversity and reduced relative abundances of Prevotella copri in children with ASD. After multiple testing corrections, we also learned that relative abundances of Feacalibacterium prausnitzii and Haemophilus parainfluenzae were lower in feces of children with ASD. Despite a relatively short list of fecal metabolites, the data in this study support that children with ASD have altered metabolite profiles in feces when compared with neurotypical children and warrant further investigation of metabolites in larger cohorts.
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3. Schiltz HK, McVey AJ, Magnus B, Dolan BK, Willar KS, Pleiss S, Karst J, Carson AM, Caiozzo C, Vogt E, Van Hecke AV. {{Examining the Links Between Challenging Behaviors in Youth with ASD and Parental Stress, Mental Health, and Involvement: Applying an Adaptation of the Family Stress Model to Families of Youth with ASD}}. {J Autism Dev Disord};2017 (Dec 23)
Raising a child with autism spectrum disorder (ASD) poses unique challenges that may impact parents’ mental health and parenting experiences. The current study analyzed self-report data from 77 parents of youth with ASD. A serial multiple mediation model revealed that parenting stress (SIPA) and parental mental health (BAI and BDI-II) appears to be impacted by challenging adolescent behaviors (SSIS-PBs) and, in turn, affect parental involvement (PRQ), controlling for social skills (SSIS-SSs). Further, the study explored the malleability of parents’ mental health over the course of a social skills intervention, and provides modest evidence that parent depressive symptoms decline across intervention. This study illustrates the importance of considering the entire family system in research on youth with ASD.
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4. Utine GE, Simsek-Kiper PO, Akgun-Dogan O, Urel-Demir G, Alanay Y, Aktas D, Boduroglu K, Tuncbilek E, Alikasifoglu M. {{Fragile x-associated premature ovarian failure in a large Turkish cohort: Findings of Hacettepe Fragile X Registry}}. {Eur J Obstet Gynecol Reprod Biol};2017 (Dec 16);221:76-80.
OBJECTIVE: To determine frequency of fragile X associated premature ovarian insufficiency (FXPOI) among Turkish premutation carriers. STUDY DESIGN: FMR1 premutation is the single most common genetic cause of POI (FXPOI). Fragile X Registry at Hacettepe University has been reviewed for the frequency of FXPOI among female premutation carriers. Since 1991 when FMR1 testing was available, 760 individuals from 243 families have been registered. Actual data on menstrual status of female premutation carriers were gathered and analysed. RESULTS: Among 314 premutation-bearing females in the cohort, 268 could be reached for an update of their menstrual history; 107 adults were 40 or younger and 156 were older than 40 years of age, whereas the remaining 5 patients were prepubertal. Among 263 postpubertal females with premutations, 90 women stopped menstruating before or at 40 years of age (premature ovarian failure – POF), constituting 34.2% of our cohort. Additionally, one carrier of a gray zone allele experienced FXPOI. History of twinning was present once in 18 women (5.7%) and twice in two women (0.6%), one of the latter interestingly bearing a full-mutation. CONCLUSIONS: FXPOI rates in the present cohort are higher than those reported in other populations. Higher FXPOI rates in Turkish premutation carriers might be a reflection of younger mean menopause age and higher POI rates in otherwise healthy Turkish women. Since POI is much more frequent among premutation carriers than in general population, testing for CGG repeat expansions in FMR1 should be included in the work-up.
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5. Yang F, Chen J, Miao MH, Yuan W, Li L, Liang H, Ehrenstein V, Li J. {{Risk of autism spectrum disorder in offspring following paternal use of selective serotonin reuptake inhibitors before conception: a population-based cohort study}}. {BMJ Open};2017 (Dec 22);7(12):e016368.
OBJECTIVE: The present study aimed to examine the association between paternal selective serotonin reuptake inhibitor (SSRI) use before conception and the risk of autism spectrum disorder (ASD) in offspring. DESIGN: A population-based cohort study. METHODS: We conducted a cohort study of 669 922 children born from 1998 to 2008, with follow-up throughout 2013. Based on Danish national registers, we linked information on paternal use of SSRIs, ASD diagnosed in children and a range of potential confounders. The children whose fathers used SSRIs during the last 3 months prior to conception were identified as the exposed. Cox regression model was used to estimate the HR for ASD in children. RESULTS: Compared with unexposed children, the exposed had a 1.62-fold higher risk of ASD (95% CI 1.33 to 1.96) and the risk attenuated after adjusting for potential confounders, especially fathers’ psychiatric conditions (HR=1.43, 95% CI 1.18 to 1.74). When extending the exposure window to 1 year before conception, the increased risk persisted in children of fathers using SSRIs only from the last year until the last 3 months prior to conception (HR=1.54, 95% CI 1.21 to 1.94) but not in children of fathers using SSRIs only during the last 3 months prior to conception (HR=1.17, 95% CI 0.75 to 1.82). We also performed stratified analyses according to paternal history of affective disorders and observed no increased ASD risk among children whose father had affective disorders. Besides, the sibling analysis showed that the ASD risk did not increase among exposed children compared with their unexposed siblings. CONCLUSIONS: The mildly increased risk of ASD in the offspring associated with paternal SSRI use before conception may be attributable to paternal underlying psychiatric indications related to SSRI use or other unmeasured confounding factors.
