Advancing paternal age and simplex autism

Department of Pshychology, Temple University, Philadelphia, PA 19122, USA.
Autism (Impact Factor: 3.5). 12/2011; 16(4):367-80. DOI: 10.1177/1362361311427154
Source: PubMed


De novo events appear more common in female and simplex autism spectrum disorder (ASD) cases and may underlie greater ASD risk in older fathers' offspring. This study examined whether advancing paternal age predicts an increase in simplex (n = 90) versus multiplex ASD cases (n = 587) in 677 participants (340 families). Whether or not controlling for maternal age, results support a significant interaction of linear paternal age and sex of the child on simplex family type. Female ASD cases were significantly more likely to be simplex as paternal age increased, but the increase for males was not significant. Findings suggest that ASD arising from non-familial, de novo events may be far less prominent in males than in females, even if more prevalent in males, due to the substantially larger number of male cases attributable to other, more strongly male-biased risk factors.

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    • "This awaits future studies employing a similar design as ours. The sex-specific neuroanatomy discovered here for high-functioning adults with autism are in line with the growing evidence of sex-specific biological profiles for the high-functioning subgroup at the levels of serum proteomics (Schwarz et al., 2011; Ramsey et al., 2012), sex steroid hormones and anthropometry (Ruta et al., 2011; Bejerot et al., 2012), and for the whole autism spectrum at the levels of genetics (Gilman et al., 2011; Puleo et al., 2012; Szatmari et al., 2012), transcriptomics (Kong et al., 2012) and early brain overgrowth (Sparks et al., 2002; Bloss and Courchesne, 2007; Schumann et al., 2009, 2010; Nordahl et al., 2011). In sum, high-functioning males and females with autism, though diagnosed by the same behavioural criteria, differ in aspects of neuroanatomy. "
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