Presents activities that use the learning cycle to engage students in meaningful inquiries in the study of Mendelian genetics. Includes content-related background and teaching tips for each phase of the learning cycle. (JRH)

Presents an activity that aims at enabling students to recognize that DNA and RNA are information molecules whose function is to store, copy, and make available the information in biological systems, without feeling overwhelmed by the specialized vocabulary and the minutia of the central dogma. (JRH)

Caregivers of 55 boys with fragile X syndrome (ages 3-12) and 57 matched controls completed five behavioral questionnaires. Principal components analysis yielded 5 behavioral clusters: abnormal language, tactile defensiveness, poor self-control, poor eye contact/shyness, and hand flapping. Boys with fragile X were four times more likely to have…

Clinical features, pathogenetic hypotheses, and symptoms of the cardio-auditory or surdo-cardiac disorder first reported by Jervell and Lange-Nielsen are described, and methods of diagnosis and treatment are presented, to alert teachers and other professionals to potentially life-threatening symptoms they may observe when working with deaf and…

This paper considers key properties of behavioral phenotypes of mental retardation syndromes, including within-syndrome variability and between-syndrome similarities and qualitative differences. The "new genetics" research requires combining data from three strategies: (1) a psychiatric approach, (2) psychometric methods, and (3) syndrome-specific…

Estimates the extent to which heredity influences perceptions of childhood family environment in a sample of 58 monozygotic and 46 dizygotic pairs of adult twins who were reared apart. The data confirm the importance of genetic factors in some, but not all, measures of family environment. Environmental influences were more important than genetic…

The mother, father, and adolescent siblings from 675 families were observed interacting in problem-solving sessions. Siblings were monozygotic twins, dyzygotic twins, or full siblings in nondivorced families and full, half, and unrelated siblings in stepfamilies. Results suggested a greater genetic component to adolescent behavior than to parent…

Pedigree analysis of 12 young adults (9 of whom had learning disabilities) indicated that learning disability (LD) was strongly familial but that the type of disability (reading or math) was not directly inherited. Autoimmune disorders were significantly correlated with LD. In seven of the LD families, adults failed to overcome earlier reading and…

Suggests that experiential canalization is appropriately applied to constraints caused by the behavior of an organism or members of its species. When other aspects of the environment propel the organism to develop in certain ways, this process reflects adaptation to the environment. Conditions for evolution of experience as a guide to development…

This study provides support for a potential subclinical marker in the executive function domain of siblings (n=18, ages 8-18) of autistic individuals, compared to learning-disabled controls. No group differences in theory-of-mind abilities were found. The need to develop more sensitive measures is discussed. (Author/JDD)

An exercise that uses a common bacterium, E. coli, in great numbers, to detect a demonstrable change in the ability of some cells to become resistant to the common antibiotic streptomycin is presented. The procedure for preparing and pouring the gradient antibiotic plates is provided. The advantages of using the Basic Fuchsin in the agar are…

Parents of 21 well-functioning autistic children were examined. Clinical details of the eight parents diagnosed as schizoid are analyzed, leading to the conclusion that one etiological factor may be a genetic predisposition to schizoid personality traits. Global and specific developmental delays in the autistic children's siblings were not found.…

The prevalence of epilepsy was correlated with the severity and type of encephalopathy of 1,023 individuals with mental retardation. A total of 326 individuals were diagnosed with epilepsy. Results indicated a low percentage of epilepsy in chromosomic-genetic and young adult encephalopathies and a high prevalence when the neurodeficit was…

A total of 127 pairs of twins completed a measure of personality at 20 and 30 years of age. Analyses revealed that variance in negative emotionality was the result of diminishing genetic influence; personality stability was the result of genetic factors; and personality change was the result of environmental factors. (BC)

Assessed the family environment and personality of 400 pairs of 59-year-old twins. Genetic influences on extraversion and neuroticism were related to genetic influences on the family environment factors of relationship and personal growth but not to the factor of system maintenance. (BC)