1. {{International Society for Autism Research News}}. {Autism Res};2009 (Jul 16);2(3):182.
2. King MD, Fountain C, Dakhlallah D, Bearman PS. {{Estimated Autism Risk and Older Reproductive Age}}. {Am J Public Health};2009 (Jul 16)
Objectives. We sought to estimate the risk for autism associated with maternal and paternal age across successive birth cohorts.Methods. We linked birth records and autism diagnostic records from the California Department of Developmental Services for children born in California between 1992 and 2000 to calculate the risk associated with maternal and paternal age for each birth cohort as well as for the pooled data.Results. The categorical risks associated with maternal age over 40 years ranged from a high of 1.84 (95% confidence interval [CI]=1.37, 2.47) to a low of 1.27 (95% CI=0.95, 1.69). The risk associated with paternal age ranged from 1.29 (95% CI=1.03, 1.6) to 1.71 (95% CI=1.41, 2.08).Conclusions. Pooling data across multiple birth cohorts inflates the risk associated with paternal age. Analyses that do not suffer from problems produced by pooling across birth cohorts demonstrated that advanced maternal age, rather than paternal age, may pose greater risk. Future research examining parental age as a risk factor must be careful to avoid the paradoxes that can arise from pooling data, particularly during periods of social demographic change.
3. Maekawa M, Iwayama Y, Nakamura K, Sato M, Toyota T, Ohnishi T, Yamada K, Miyachi T, Tsujii M, Hattori E, Maekawa N, Osumi N, Mori N, Yoshikawa T. {{A novel missense mutation (Leu46Val) of PAX6 found in an autistic patient}}. {Neurosci Lett};2009 (Jul 13)
The paired box 6 (PAX6) is a transcription factor expressed early in development, predominantly in the eye, brain and pancreas. Mutations in PAX6 are responsible for eye abnormalities including aniridia, and it is also known that some PAX6 mutations result in autism with incomplete penetrance. We resequenced all the exons and flanking introns of PAX6 in 285 autistic patients in the Japanese, with the possibility that novel mutations may underlie autism. Fifteen different polymorphisms were identified: 13 are novel, and 2 were previously reported (rs667773 and rs3026393). Among the novel ones, there is one missense mutation that was found in a patient: 136C>G (Leu46Val) (single nucleotide polymorphism ID « ss130452457 » is temporarily assigned). Leu46 is extremely conserved from fly to human, and we did not detect Val46 in 2,120 nonautistic subjects. The autistic patient carrying this heterozygous mutation showed reduced vision, photophobia and eyelid ptosis, but no other ocular abnormality such as aniridia. Our findings suggest the necessity of further studies on the causal relationship between PAX6 and autism.
4. Mayes SD, Calhoun SL, Murray MJ, Morrow JD, Yurich KK, Mahr F, Cothren S, Purichia H, Bouder JN, Petersen C. {{Comparison of Scores on the Checklist for Autism Spectrum Disorder, Childhood Autism Rating Scale, and Gilliam Asperger’s Disorder Scale for Children with Low Functioning Autism, High Functioning Autism, Asperger’s Disorder, ADHD, and Typical Development}}. {J Autism Dev Disord};2009 (Jul 16)
Reliability and validity for three autism instruments were compared for 190 children with low functioning autism (LFA), 190 children with high functioning autism or Asperger’s disorder (HFA), 76 children with attention deficit hyperactivity disorder (ADHD), and 64 typical children. The instruments were the Checklist for Autism Spectrum Disorder (designed for children with LFA and HFA), Childhood Autism Rating Scale (CARS) for children with LFA, and Gilliam Asperger’s Disorder Scale (GADS). For children with LFA or ADHD, classification accuracy was 100% for the Checklist and 98% for the CARS clinician scores. For children with HFA or ADHD, classification accuracy was 99% for the Checklist and 93% for the GADS clinician scores. Clinician-parent diagnostic agreement was high (90% Checklist, 90% CARS, and 84% GADS).
5. Pastural E, Ritchie S, Lu Y, Jin W, Kavianpour A, Khine Su-Myat K, Heath D, Wood PL, Fisk M, Goodenowe DB. {{Novel plasma phospholipid biomarkers of autism: Mitochondrial dysfunction as a putative causative mechanism}}. {Prostaglandins Leukot Essent Fatty Acids};2009 (Jul 14)
Autism is a neurological disorder that manifests as noticeable behavioral and developmental abnormalities predominantly in males between the ages of 2 and 10. Although the genetics, biochemistry and neuropathology of this disease have been extensively studied, underlying causal factors to this disease have remained elusive. Using a longitudinal trial design in which three plasma samples were collected from 15 autistic and 12 non-autistic age-matched controls over the course of 1 year, universal and unambiguous alterations in lipid metabolism were observed. Biomarkers of fatty acid elongation and desaturation (poly-unsaturated long chain fatty acids (PUFA) and/or saturated very long chain fatty acids (VLCFA)-containing ethanolamine phospholipids) were statistically elevated in all autistic subjects. In all 8 of the affected/non-affected sibling pairs, the affected sibling had higher levels of these biomarkers than the unaffected sibling. Exposure of neurons, astrocytes and hepatocytes in vitro to elevated extracellular glutamate levels resulted in lipid biomarker changes indistinguishable from those observed in autistic subjects. Glutamate stress also resulted in in vitro decreased levels of reduced glutathione (GSH), methionine and cysteine, in a similar way to the decreases we observed in autism plasma. Impaired mitochondrial fatty acid oxidation, elevated plasma VLCFAs, and glutamate toxicity as putative causal factors in the biochemistry, neuropathology, and gender bias in autism are discussed.
6. Pelc K, Dan B. {{Postural cortical myoclonus during gait in Rett syndrome}}. {Epilepsy Behav};2009 (Jul 14)
7. Senju A, Southgate V, White S, Frith U. {{Mindblind Eyes: An Absence of Spontaneous Theory of Mind in Asperger Syndrome}}. {Science};2009 (Jul 16)
Adults with Asperger syndrome can understand mental states such as desires and beliefs (mentalizing) when explicitly prompted to do so, despite having impairments in social communication. We directly tested the hypothesis that such individuals nevertheless fail to mentalize spontaneously. To this end, we used an eye tracking task that has revealed the spontaneous ability to mentalize in typically developing infants. We showed that, like infants, neurotypical adults’ (N = 17) eye movements anticipated an actor’s behavior on the basis of her false belief. This was not the case for individuals with Asperger syndrome (N = 19). Thus, these individuals do not attribute mental states spontaneously, but may be able to do so in explicit tasks through compensatory learning.
