Genetic and environmental influences on prereading skills in preschool and on early reading and spelling development at the end of kindergarten were compared among samples of identical and fraternal twins from the U.S. (Colorado), Australia, and Scandinavia. Mean comparisons revealed significantly lower preschool print knowledge in Scandinavia,…

Numerous studies have examined the etiology of the association between reading difficulties and attention-deficit hyperactivity disorder (ADHD) in school-age children, but little is known about the relation between prereading skills and ADHD behaviors prior to the beginning of formal reading instruction. A population-based sample of 809 pairs of…

Genetic factors are important contributors to language and learning disorders, and discovery of the underlying genes can help delineate the basic neurological pathways that are involved. This information, in turn, can help define disorders and their perceptual and processing deficits. Initial molecular genetic studies of dyslexia, for example,…

Taking into account the historic transitions and progressions in agricultural science, this article examines the emergence of the phenomenon of agricultural biotechnology. It identifies pivotal sites of tension between agricultural biotechnology and alternative approaches to agriculture. The article identifies two distinct sources of contemporary…

Most dominant theories of crime and criminality underscore the saliency of the family in the etiology of offending behaviors. Recently, a small pool of research has suggested that elements of the family, especially parents, do not have a lasting impact on children. This line of inquiry argues that once the effects that the child has on the family…

This study investigated knowledge of binding and raising in two groups of children with Williams syndrome (WS), 6-12 and 12-16-years-old, compared to typically developing (TD) controls matched on non-verbal MA, verbal MA, and grammar. In typical development, difficulties interpreting pronouns, but not reflexives, persist until the age of around 6,…

The aim of the current study was to investigate expressive affect in children with Williams syndrome (WS) in comparison to typically developing children in an experimental task and in spontaneous speech. Fourteen children with WS, 14 typically developing children matched to the WS group for receptive language (LA) and 15 typically developing…

Objective: Risk criteria for the Checklist for Autism in Toddlers (CHAT) and modified risk criteria (i.e. the Denver Criteria) were compared in a group of children with fragile X syndrome (FXS) and autism. Method: Participants were 17 children aged 2-4 years with DNA confirmation of FXS. Four children had autism and 13 children did not. Results:…

Background: The main objective of this study was to develop a comprehensive, empirical model that would allow the reorganization of the structure of the pervasive developmental disorder symptom phenotype through factor analysis into more homogeneous dimensions. Method: The sample consisted of 209 children with pervasive developmental disorder…

This booklet, one of six in the Living Things Science series, presents activities about heredity and genetics which address basic "Benchmarks" suggested by the American Association for the Advancement of Science for the Living Environment for grades 3-5. Contents include background information, vocabulary (in English and Spanish),…

A variety of databases were searched for the compilation of this bibliography on adolescent alcoholism, reflecting the psychological and socioeconomic aspects covered. Nine hundred and twenty-eight citations in English and foreign languages for the period January 1986 through April 1992 were included. For journal articles written in a foreign…

The hazards posed by new techniques of genetic manipulation have prompted scientists to regulate and in some cases restrict their own basic investigations. Describes some possible applications of the new techniques and outlines the established research guidelines. (GS)