Structural differences between females and males (as compared to typical controls) have been observed (Sandu et al., 2008; Altarelli et al., 2013, 2014; Clark et al., 2014; Evans et al., 2014; Su et al., 2018), and in a separate line of investigation, it has been demonstrated that genetic risk for dyslexia may be mediated in part by estrogen and estrogen receptors (Massinen et al., 2009; Tammimies et al., 2012). This evidence concerns the gene ESR1 and dyslexia.