FOXP2 and childhood apraxia of speech: FOXP2 mutations account for only a small proportion of non-syndromic forms of apraxic speech, referred to as childhood apraxia of speech (CAS; MacDermot et al., 2005; Laffin et al., 2012) and have not been found in other forms of SSD or in LI (Meaburn et al., 2002; Newbury et al., 2002; O’Brien et al., 2003), a disorder that is often comorbid with SSD.