Autism Speaks, the world’s largest autism science and advocacy organization, joined in announcing significant findings from the largest known study of younger siblings of children who had a verified diagnosis of autism spectrum disorder (ASD). This study, based on data from the Autism Speaks High Risk Baby Siblings Research Consortium (BSRC) and led by investigators from the UC Davis MIND Institute, was published online today in the journal Pediatrics and will appear in the September issue.
The “Recurrence Risk for Autism Spectrum Disorders: A Baby Siblings Research Consortium Study” found that 19 percent of younger siblings of children with ASD developed autism, a rate significantly higher than the general population. If there were two children with ASD in the family, the risk of the third sibling developing ASD increased to more than 32 percent. The study found that the risk of an ASD diagnosis for male infants who had an older sibling with ASD was almost three times greater than the risk for female infants (26 percent compared to 9 percent). The study did not find any increase in risk associated with the gender of the older sibling, severity of the older sibling’s symptoms, or other parent characteristics such as parental age, socio-economic status or race/ethnicity.
“By pulling together data from many investigators who are studying infant siblings of children with autism, these results offer a more accurate estimate of the recurrence rate for autism in siblings,” says Autism Speaks Chief Science Officer Geraldine Dawson, Ph.D. “Surprisingly, the rate is much higher than previous estimates. This points to the important need for closely monitoring and screening siblings so that they can be offered intervention as early as possible to ensure the best possible outcome.”
A pandemic of ailments called the “allergic march”—the gradual acquisition of overlapping allergic diseases that commonly begins in early childhood—has frustrated both parents and physicians. For the last three decades, an explosion of eczema, food allergies, hay fever, and asthma have afflicted children in the United States, the European Union, and many other countries.
What causes the march and how to derail it has remained elusive. Now, in this week’s Nature, David Artis, PhD, an associate professor of Microbiology at the Perelman School of Medicine at the University of Pennsylvania, and a team of collaborating international scientists, identified that expression of the protein TSLP may influence susceptibility to multiple allergic diseases by regulating the maturation of basophils, an uncommon type of white blood cell. Specifically, TSLP elicits the maturation of a population of distinct basophils that promotes allergic inflammation.
“A fundamental question regarding the allergic march is if a child has eczema, for example, which is associated with TSLP production in skin cells, why would some of those children subsequently be more susceptible to other allergic diseases at different sites of the body such as the gut or the lung?” asks Artis. “Although we have known that TSLP is associated with allergic diseases for many years, how this biological messenger might influence multiple allergic diseases has been a puzzle.”