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The article focuses on the evolution of thinking about dyslexia over the past 28 years. The characteristics of dyslexia include difficulties with accurate and/or fluent word recognition and poor spelling and decoding abilities. It has long been recognized that dyslexia is inherited. A research revealed that phonological coding demonstrated the highest degree of heritability among skills underlying reading and spelling disability. A research conducted for fifteen years involving animal models revealed that abnormal neuronal migration leads to cortical malformations, which, in turn, produce a variety of cognitive deficits similar to those observed in readers with dyslexia. Recent cross-cultural studies have identified differences in the incidence and severity of dyslexia in different language cultures and has also provided at the same time additional insights into the reciprocation of orthographies with deficits in phonological processing. The precursors of dyslexia are discussed from the point of view of research into genetic inheritance, perceptual processing efficiency and the formation and function of brain structures.