Screening

For the First Time, A Census of Autistic Adults

Source: 
Time Magazine
Date Published: 
October 3, 2009
Abstract: 

On Sept. 22, England's National Health Service (NHS) released the first study of autism in the general adult population. The findings confirm the intuitive assumption: that ASD is just as common in adults as it is in children. Researchers at the University of Leicester, working with the NHS Information Center found that roughly 1 in 100 adults are on the spectrum — the same rate found for children in England, Japan, Canada and, for that matter, New Jersey.

Researchers identify how PCBs may alter in utero, neonatal brain development

Source: 
PLoS-Biology, Pessah, et al
Date Published: 
April 2009
Year Published: 
2009

In three new studies — including one appearing in the Public Library of Science - Biology (PLoS - Biology) — UC Davis researchers provide compelling evidence of how low levels of polychlorinated biphenyls (PCBs) alter the way brain cells develop.

The findings could explain at last — some 30 years after the toxic chemicals were banned in the United States — the associations between exposure of the developing nervous system to PCBs and behavioral deficits in children.

 

Two-year-olds with autism orient to non-social contingencies rather than biological motion

Source: 
Nature, Klin, Lin, Gorrindo, Ramsay, Jones
Date Published: 
March 2009
Year Published: 
2009

Typically developing human infants preferentially attend to biological motion within the first days of life. This ability is highly conserved across species and is believed to be critical for filial attachment and for detection of predators. The neural underpinnings of biological motion perception are overlapping with brain regions involved in perception of basic social signals such as facial expression and gaze direction, and preferential attention to biological motion is seen as a precursor to the capacity for attributing intentions to others. However, in a serendipitous observation, we recently found that an infant with autism failed to recognize point-light displays of biological motion, but was instead highly sensitive to the presence of a non-social, physical contingency that occurred within the stimuli by chance. This observation raised the possibility that perception of biological motion may be altered in children with autism from a very early age, with cascading consequences for both social development and the lifelong impairments in social interaction that are a hallmark of autism spectrum disorders. Here we show that two-year-olds with autism fail to orient towards point-light displays of biological motion, and their viewing behavior when watching these point-light displays can be explained instead as a response to non-social, physical contingencies—physical continimplications for understanding the altered neurodevelopmental trajectory of brain specialization in autism.

Absence of Preferential Looking to the Eyes of Approaching Adults Predicts Level of Social Disability in 2-year old toddlers with Autism Spectrum Disorder

Source: 
Archives of General Psychiatry, Jones, Carr, et al
Date Published: 
2008

Looking at the eyes of others is important in early social development and in social adaptation throughout one's life span. Our results indicate that in 2-year-old children with autism, this behavior is already derailed, suggesting critical consequences for development but also offering a potential biomarker for quantifying syndrome manifestation at this early age.

Recurrent 16p11.2 Microdeletions in Autism

Source: 
Human Molecular Genetics, Kumar, KaraMohamed, et al
Date Published: 
2008
Year Published: 
2008

Autism is a childhood neurodevelopmental disorder with a strong genetic component, yet the identification of autism susceptibility loci remains elusive. We investigated 180 autism probands and 372 control subjects by array comparative genomic hybridization (aCGH) using a 19K whole-genome tiling path bacterial artificial chromosome microarray to identify submicroscopic chromosomal rearrangements specific to autism. We discovered a recurrent 16p11.2 microdeletion in two probands with autism and none in controls. The deletion spans approximately 500-kb and is flanked by approximately 147-kb segmental duplications (SDs) that are >99% identical, a common characteristic of genomic disorders. We assessed the frequency of this new autism genomic disorder by screening an additional 532 probands and 465 controls by quantitative PCR and identified two more patients but no controls with the microdeletion, indicating a combined frequency of 0.6% (4/712 autism versus 0/837 controls; Fisher exact test P = 0.044). We confirmed all 16p11.2 deletions using fluorescence in situ hybridization, microsatellite analyses and aCGH, and mapped the approximate deletion breakpoints to the edges of the flanking SDs using a custom-designed high-density oligonucleotide microarray. Bioinformatic analysis localized 12 of the 25 genes within the microdeletion to nodes in one interaction network. We performed phenotype analyses and found no striking features that distinguish patients with the 16p11.2 microdeletion as a distinct autism subtype. Our work reports the first frequency, breakpoint, bioinformatic and phenotypic analyses of a de novo 16p11.2 microdeletion that represents one of the most common recurrent genomic disorders associated with autism to date.

Mortality and Causes of Death in Autism Spectrum Disorders: An Update

Source: 
Autism, Mouridsen, Bronnum-Hansen, et al
Date Published: 
2008

This study compared mortality among Danish citizens with autism spectrum disorders (ASDs) with that of the general population. A clinical cohort of 341 Danish individuals with variants of ASD, previously followed over the period 1960-93, now on average 43 years of age, were updated with respect to mortality and causes of death. Standardized mortality ratios (SMRs) were calculated for various times after diagnosis. In all, 26 persons with ASD had died, whereas the expected number of deaths was 13.5. Thus the mortality risk among those with ASD was nearly twice that of the general population. The SMR was particularly high in females. The excess mortality risk has remained unchanged since our first study in 1993. Eight of the 26 deaths were associated with epilepsy and four died from epilepsy. Future staff education should focus on better managing of the complex relationships between ASD and physical illness to prevent avoidable deaths.

Screening Strategies for Autism Spectrum Disorders in Pediatric Primary Care

Source: 
Journal of Developmental and Behavioral Pediatrics, Pinto-Martin, Young, Mandell, Poghosyan, Giarelli, Levy
Date Published: 
2008
Year Published: 
2008

Two strategies have been proposed for early identification of children with autism spectrum disorders (ASD): (1) using a general screening tool followed by an ASD-specific screening tool for those who screen positive on the former or (2) using an ASD-specific tool for all children. The relative yield of these two strategies has not been examined. 

This study compared the number of children identified at risk for ASD at their well child visits between the ages of 18 and 30 months using a general developmental screening tool and an autism-specific screening tool. 

The PEDS missed the majority of children who screened positive for ASD on the M-CHAT, suggesting that these two tools tap into very different domains of developmental concerns. The findings support the use of an ASD-specific tool for all children in conjunction with regular standardized developmental screening.