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Background: Autism spectrum disorders (ASD) are a group of severe childhood neurodevelopmental disorders with still unknown etiology. One of the most frequently reported associations is the presence of recurrent de novo or inherited microdeletions and microduplications on chromosome 16p11.2. The analysis of rare variations of 8 candidate genes among the 27 genes located in this region suggested SEZ6L2 as a compelling candidate. Methodology/Principal Findings: We further explored the role of SEZ6L2 variations by screening its coding part in a group of 452 individuals, including 170 patients with ASD and 282 individuals from different ethnic backgrounds of the Human Genome Diversity Panel (HGDP), complementing the previously reported screening. We detected 7 previously unidentified non-synonymous variations of SEZ6L2 in ASD patients. We also identified 6 non-synonymous variations present only in HGDP. When we merged our results with the previously published, no enrichment of non-synonymous variation in SEZ6L2 was observed in the ASD group compared with controls. Conclusions/Significance: Our results provide an extensive ascertainment of the genetic variability of SEZ6L2 in human populations and do not support a major role for SEZ6L2 sequence variations in the susceptibility to ASD. [ABSTRACT FROM AUTHOR]

Background: Autism spectrum disorders (ASD) are severe neurodevelopmental disorders with the male:female ratio of 4:1, implying the contribution of X chromosome genetic factors to the susceptibility of ASD. The ribosomal protein L10 (RPL10) gene, located on chromosome Xq28, codes for a key protein in assembling large ribosomal subunit and protein synthesis. Two non-synonymous mutations of RPL10, L206M and H213Q, were identified in four boys with ASD. Moreover, functional studies of mutant RPL10 in yeast exhibited aberrant ribosomal profiles. These results provided a novel aspect of disease mechanisms for autism -- aberrant processes of ribosome biosynthesis and translation. To confirm these initial findings, we re-sequenced RPL10 exons and quantified mRNA transcript level of RPL10 in our samples. Methods: 141 individuals with ASD were recruited in this study. All RPL10 exons and flanking junctions were sequenced. Furthermore, mRNA transcript level of RPL10 was quantified in B lymphoblastoid cell lines (BLCL) of 48 patients and 27 controls using the method of SYBR Green quantitative PCR. Two sets of primer pairs were used to quantify the mRNA expression level of RPL10: RPL10-A and RPL10-B. Results: No non-synonymous mutations were detected in our cohort. Male controls showed similar transcript level of RPL10 compared with female controls (RPL10-A, U = 81, P = 0.7; RPL10-B, U = 61.5, P = 0.2). We did not observe any significant difference in RPL10 transcript levels between cases and controls (RPL10-A, U = 531, P = 0.2; RPL10-B, U = 607.5, P = 0.7). Conclusion: Our results suggest that RPL10 has no major effect on the susceptibility to ASD. [ABSTRACT FROM AUTHOR]

Background: Reliable, valid and easily administered screening instruments would greatly facilitate large-scale neuropsychiatric research.Aims: To test a parent telephone interview focused on autism - tics, attention-deficit hyperactivity disorder (ADHD) and other comorbidities (A-TAC).Method: Parents of 84 children in contact with a child neuropsychiatric clinic and 27 control children were interviewed. Validity and interrater and test - retest reliability were assessed.Results: Interrater and test - retest reliability were very good. Areas under receiver operating characteristics curves between interview scores and clinical diagnoses were around 0.90 for ADHD and autistic spectrum disorders, and above 0.70 for tics, learning disorders and developmental coordination disorder. Using optimal cut-off scores for autistic spectrum disorder and ADHD, good to excellent kappa levels for interviews and clinical diagnoses were noted.Conclusions: The A-TAC appears to be a reliable and valid instrument for identifying autistic spectrum disorder, ADHD, tics, learning disorders and developmental coordination disorder. [ABSTRACT FROM AUTHOR]

Many studies have supported a genetic etiology for autism. Here we report mutations in two X-linked genes encoding neuroligins NLGN3 and NLGN4 in siblings with autism-spectrum disorders. These mutations affect cell-adhesion molecules localized at the synapse and suggest that a defect of synaptogenesis may predispose to autism. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of the present study was to assess which types of neuropsychological deficits appear to be most commonly associated with autism spectrum disorders (ASD) and attention-deficit/hyperactivity disorder (ADHD) in adults. The effect of the combination of ASD with ADHD (ASD/ADHD) was also studied. One hundred and sixty-one adult individuals (≥18 years of age) were included in the study. None had full scale IQ less than 71. The neuropsychological investigations included measures of intellectual ability, learning and memory, attention/executive function and theory of mind. The three diagnostic groups showed reduced performance in most cognitive domains. However, within these domains differentiating distinct features could be seen. The dysfunctions of the ASD/ADHD group cannot be seen as a summary of the dysfunctions found in the ASD and ADHD groups. The ADHD seemed to have the most severe neuropsychological impairments of the three groups. No domain-specific deficit typical of any of the diagnostic groups was found. [ABSTRACT FROM AUTHOR]