Evaluation of Genetic Explanations of Reading and Learning Problems

Abstract

Since the end of the last century there have been studies of reading and learning problems which have concluded that a considerable proportion of these difficulties are inherited. This conclusion has been reaffirmed in recent investigations and explications of reading and learning "disabilities." Evidence for a heritability explanation has come from two sources: family and twin studies. An examination of these studies, however, demonstrates that although they appear to use the "scientific method" and are replete with quantified analysis, in fact they offer little substantial evidence for their conclusions. Moreover, they violate principles of logic and hypothesis testing to such an extent that they must be considered to be not merely inadequately scientific, but, indeed, pseudoscientific. Unfortunately, lack of evidence and egregious conclusions have not prevented the dissemination of heritability explanations among professionals and the public.