Journal of Learning Disabilities 43(4) 308–321 © Hammill Institute on Disabilities 2010 Reprints and permission: sagepub.com/journalsPermissions.nav DOI: 10.1177/0022219410369096 http://journaloflearningdisabilities .sagepub.com Language Development, Literacy Skills, and Predictive Connections to Reading in Finnish Children With and Without Familial Risk for Dyslexia Minna Torppa 1 , Paula Lyytinen 1 , Jane Erskine 1 , Kenneth Eklund 1 , and Heikki Lyytinen 1 Abstract Discriminative language markers and predictive links between early language and literacy skills were investigated retrospec- tively in the Jyväskylä Longitudinal Study of Dyslexia in which children at familial risk for dyslexia have been followed from birth. Three groups were formed on the basis of 198 children’s reading and spelling status. One group of children with reading disability (RD; n = 46) and two groups of typical readers from nondyslexic control (TRC; n = 84) and dyslexic families (TRD; n = 68) were examined from age 1.5 years to school age.The RD group was outperformed by typical readers on numerous language and literacy measures (expressive and receptive language, morphology, phonological sensitivity, RAN, and letter knowledge) from 2 years of age onward. The strongest predictive links emerged from receptive and expressive language to reading via measures of letter naming, rapid naming, morphology, and phonological awareness. Keywords dyslexia, longitudinal study, reading development, early language development Reading ability requires the coordination of a number of component skills, each of which has developed over many years before reading skill itself can emerge. Several studies (e.g., Pennington & Lefly, 2001; Puolakanaho et al., 2007, 2008; Scarborough, 1990, 1998; Snowling, Gallagher, & Frith, 2003) confirm that school beginners who have weaker verbal abilities and literacy knowledge at an early age are much more likely to experience difficulties in learning to read than their classmates. The problems of disabled readers usually manifest as difficulties in the acquisition of basic reading subskills such as word identification and phonological (letter-sound) decod- ing (Vellutino, Fletcher, Snowling, & Scanlon, 2004). Previous findings have revealed that the strongest early predictors of subsequent poor reading are phonological awareness and letter knowledge (e.g., H. Lyytinen et al., 2004; Pennington & Lefly, 2001; Puolakanaho et al., 2007). In addition to phonological awareness and letter naming, also other early skills have been shown to differentiate poor readers from typically achieving readers, such as rapid serial naming (e.g., DeJong & van der Leij, 2003; H. Lyytinen, Erskine, et al., 2006; Wolf, Bowers, & Biddle, 2000), vocabulary (e.g., Scarborough, 1990), verbal learning (e.g., Carroll & Snowling, 2004), verbal memory (e.g., H. Lyytinen et al., 2004; Snowling et al., 2003), and pseudoword or nonword repetition (e.g., H. Lyytinen et al., 2004; Snowling et al., 2003; van Alphen et al., 2004). Reading disability or dyslexia runs in families (e.g., DeFries & Gillis, 1993; Hallgren, 1950; Olson & Byrne, 2005), and by conducting a prospective study of children who are at high risk of dyslexia due to family history, we can effectively examine the role of oral language development in reading disabilities. Scarborough’s (1990) study was the first prospective dyslexia investigation in which English language development was followed from the age of 2.5 years until the age at which the children’s reading status could be confirmed. In Scarborough’s study, 65% of those children from families with genetic risk of dyslexia could be classified as reading disabled by age 8. Syntactic and speech production abilities differentiated the groups at 2.5 years and vocabulary skills from 3 years onwards. By age 5, children who went on to receive a diagnosis of dyslexia had poor letter knowledge and poorly developed phonological awareness and expressive 1 University of Jyväskylä, Jyväskylä, FINLAND Corresponding Author: Minna Torppa, Department of Psychology, PO. Box 35, 40014 University of Jyväskylä Finland tel. +358-14-2602897 fax. +358-14-2604400 Email: minna.p.torppa@jyu.fi