numbers found for families with a history of speech-language pathology suggests that there is some underlying genetic/biological factor contributing to the development of the problem.
In a similar study, Tomblin (1989) used a questionnaire concerning the history of treatment of developmental language disorder to evaluate the prevalence of these problems within the immediate family members of second-grade children with and without language impairment. The data obtained from these families revealed strong evidence that such language problems are not randomly distributed across families but rather tend to concentrate within families.
It was further found that although all family members of the language-impaired second graders demonstrated substantially increased odds for language impairment over those who came from families with normal second graders, a considerable range of increased odds for language impairment existed among the family members. Specifically, brothers and to a lesser degree sisters had a higher familial association with language impairment than did the parents. What this study shows is that the genetic contribution to the development of language disorder is not set and can be affected by a number of other factors so as to produce a range of impairment.
This point is made in a study by Robinson (1991) who examined eighty two children with severe and persistent specific speech and language disorders, including receptive/expressive disorders. As with Paul's study, Robinson found that those families with a history of speech-language problem had more children with language disorder than did families with no history of the problem. However, it was also observed that in several cases, the disorder was the result of non-genetic factors such as seizures arising from a childhood illness.
Paul (1991) also notes that there appears to be some correlation with receptive/expressive language disorder and hyperac...