Diagnostic Disparities

Children Conceived in Winter have a Greater Risk of Autism, Study Finds

Source: 
Medical News Today
Date Published: 
May 5, 2011
Abstract: 

An examination of the birth records of the more than 7 million children born in the state of California during the 1990s and early 2000s has found a clear link between the month in which a child is conceived and the risk of that child later receiving a diagnosis of autism. Among the children included in the study, those conceived during winter had a significantly greater risk of autism, the study found.

Prevalence of Autism Spectrum Disorders in a Total Population Sample

Source: 
Autism Science Foundation Blog
Date Published: 
May 9, 2011
Abstract: 

A long-awaited study of autism prevalence in Korea came out today in the The American Journal of Psychiatry. Results showed a much higher prevalence estimate than previously found, along with a large fraction of the autistic students previously unidentified and being educated in regular education programs.

Socioeconomics Playing Reduced Role in Autism Diagnoses

Source: 
Medical News Today
Date Published: 
April 6, 2011
Abstract: 

While there is an increasing equality in terms of the likelihood that children from communities and families across the socioeconomic spectrum will be diagnosed with autism, a new study finds that such factors still influence the chance of an autism diagnosis, though to a much lesser extent than they did at the height of rising prevalence.

Children With Autistic Traits Remain Undiagnosed

Source: 
Science Daily
Date Published: 
March 22, 2010
Abstract: 

There has been a major increase in the incidence of autism over the last twenty years. While people have differing opinions as to why this is (environment, vaccines, mother's age, better diagnostic practice, more awareness etc.) there are still many children who have autistic traits that are never diagnosed clinically. Therefore, they do not receive the support they need through educational or health services.

No Autism Epidemic

Source: 
Medical News Today
Date Published: 
March 1, 2011
Abstract: 

A study conducted in 1998 found that autism occurred in 0.05 per cent of Norwegian children. The figures from the "Barn i Bergen" project could therefore be interpreted to mean that the incidence of autism has risen dramatically. However, Ms Posserud thinks it is important to downplay the difference in results. Her conclusion is that the rise in ASD can be explained mainly by the use of more thorough mapping methods and, consequently, that we are not seeing the emergence of an autism epidemic

Researchers Reveal First Autism Candidate Gene That Demonstrates Sensitivity to Sex Hormones

Source: 
Journal of Molecular Psychiatry, Hu et al.
Date Published: 
March 2011
Year Published: 
2011

 

George Washington University researchers have found that male and female sex hormones regulate expression of an important gene in neuronal cell culture through a mechanism that could explain not only higher levels of testosterone observed in some individuals with autism, but also why males have a higher incidence of autism than females.

The gene, RORA, encodes a protein that works as a "master switch" for gene expression, and is critical in the development of the cerebellum as well as in many other processes that are impaired in autism. Dr. Hu's earlier research found that RORA was decreased in the autistic brain. In this study, the research group demonstrates that aromatase, a protein that is regulated by RORA, is also reduced in autistic brains.

This is significant because aromatase converts testosterone to estrogen. Thus, a decrease in aromatase is expected to lead in part to build up of male hormones that, in turn, further decrease RORA expression, as demonstrated in this study using a neuronal cell model. On the other hand, female hormones were found to increase RORA in the neuronal cells. The researchers believe that females may be more protected against RORA deficiency not only because of the positive effect of estrogen on RORA expression, but also because estrogen receptors, which regulate some of the same genes as RORA, can help make up for the deficiency in RORA.

The Tragedy Of The Fraudulent MMR Autism Link, A Personal Story

Source: 
Medical News Today
Date Published: 
February 7, 2011
Abstract: 

Medical journalist recaps his struggle to determine if vaccinations caused his son to be diagnosed with Asperger's Syndrome concluding that it would not have made the slightest bit of difference if we had refused to vaccinate when our son was small, claiming any conspiracy theories are not based on any compelling data.

Autism and Increased Paternal Age Related Changes in Global Levels of Gene Expression Regulation

Source: 
PloS One, Alter et al.
Date Published: 
February 2011
Year Published: 
2011

This study, performed by researchers at the University of Pennsylvania, analyzed the level of gene expression in children with autism, compared with a control group. The researchers hypothesized that the variability in the pattern of the overall of gene expression levels would be associated with variability in hippocampal-dependent behaviors, which include short-term memory and spatial navigation. Additionally, the group tested whether increased paternal age was associated with variance of gene expression. A decrease in the variability of gene expression levels was associated with the diagnosis of autism and increased paternal age. The research team believes this change to be caused by the down-regulation of gene expression pathways involved in protein synthesis regulation in the blood of children with autism and children with older fathers. Thus, the researchers concluded that alterations at the gene level of gene expression regulation are related to autism and increased paternal age.

Autism Risk Linked To Space Between First And Second Pregnancy

Source: 
Medical News Today
Date Published: 
January 10, 2011
Abstract: 

A second child is three times more likely to be diagnosed with autism if they are born within twelve months of their siblings, compared to those born three or more years apart, researchers from the Lazarsfeld Center for the Social Sciences at Columbia University, New York revealed in the journal Pediatrics. The investigators gathered information on 660,000 second children born in California between 1992 to 2002.

Prevalence of Autism According to Maternal Immigrant Status and Ethnic Origin

Source: 
Acta Psychiatrica Scandanavia, M.-J Dealberto
Date Published: 
January 2011
Year Published: 
2011

This study examined the rates of autism according to maternal immigrant status and ethnic origins based on the vitamin D insufficiency hypothesis, which proposes that maternal vitamin D insufficiency during pregnancy could be associated with autism. The study provided further support to the association between maternal immigrant status and an increased risk of autism. In addition, although more complex, ethnic origin was shown to have an effect on the rates of autism; the study found that black ethnicity demonstrated a higher incidence of autism, particularly when considering autism associated with mental retardation. The results found in the study are consistent with the maternal vitamin D insufficiency hypothesis. To understand the effect of maternal vitamin D insufficiency during pregnancy on the development of the fetal brain, neurobiological studies are necessary.