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The goals, prospects and methods of the Longitudinal Israeli Study of Twins (LIST) are described. This study is interested in children's prosocial development from phenotypic, genetic and environmental perspectives. It focuses on measuring prosociality with a multi-trait multi-method approach, and relating it to children's general cognitive and sociocognitive abilities, and to parenting in the family. Other variables of interest such as children's temperament and parental values are discussed, as are ideas for further research. [ABSTRACT FROM AUTHOR]

The Wisconsin Twin Panel is based on the population of all twins born in the state of Wisconsin, United States. Our research focus is the etiology and developmental course of early emotions, temperament, childhood anxiety and impulsivity, the autism spectrum, auditory and tactile sensory sensitivity, and related psychobiological and behavioral phenotypes. We employ a range of research methods including structured interviews with caregivers, observer ratings, child self-report, home-based behavioral batteries, biological measures of basal and reactive cortisol, palm prints, birth records, genotyping, cognitive testing, and questionnaires. Reported results highlight the utility of employing multiple modes of assessment when studying child development and psychopathology. [ABSTRACT FROM AUTHOR]

Background: Interpersonal dependence is thought to be important in a number of physical and psychological disorders. There are several developmental theories that suggest environmental influences in childhood are important.Method: A twin study methodology was used to look at the genetic and environmental influences on interpersonal dependence as measured by a sub-scale of the Interpersonal Dependency Inventory with a population-based sample of 2230 twins.Results: Psychometric analysis revealed that this was a stable measure and that there was a substantial degree of construct validity. Both univariate and longitudinal twin analysis suggested that there was a modest genetic influence and a large, specific environment influence on interpersonal dependency as measured by this scale. The longitudinal analysis revealed that the genetic influence was stable over the time-scale sampled and the environmental influence was moderately stable.Conclusions: This finding is at odds with theories that suggest shared environment is important in the aetiology of interpersonal dependency. [ABSTRACT FROM AUTHOR]

Data are presented from 157 monozygotic and 143 dizygotic female twin pairs of reproductive age who completed a self-report questionnaire on the premenstrual syndrome (PMS). For global PMS scores, the correlation coefficient for the monozygotic twins (0.55) was double that of the dizygotic ones (0.28). The results are consistent with the hypothesis that aggregation for global PMS scores is determined by genetic factors acting additively over a number of loci. Two alternative explanations are suggested: that monozygotic twins share greater environmental similarities than dizygotic ones; or that PMS scores may be a reflection of some other underlying characteristic (such as neuroticism), which is itself genetically determined. [ABSTRACT FROM AUTHOR]

A pair of identical twins for whom long-term follow-up information was available progressed concordantly from typical `affective illness' to process schizophrenia. We discuss a possible genetic basis for a certain form of schizophrenia which may present typical affective features in the initial phase of process schizophrenia. [ABSTRACT FROM AUTHOR]

This paper presents a well-documented case of monozygotic male twins concordant for infantile autism, with a twelve-year follow-up. Assessments include birth records, laboratory studies, physical measurements, psychometrics and quantifiable behavioural ratings by independent raters using multiple scales. Possible aetiological factors of infantile autism, as well as outcome are discussed. [ABSTRACT FROM AUTHOR]

The National Academy of Sciences-National Research Council (NAS-NRC) Twin Registry is one of the oldest, national population-based twin registries in the United States. It consists of 15,924 white male twin pairs born in the years 1917 to 1927 (inclusive), both of whom served in the armed forces, mostly during World War II. This article updates activity in this registry since the earlier 2002 article in Twin Research. The results of clinically based studies on dementia, Parkinson's disease, age-related macular degeneration, and primary osteoarthritis were published, as well as articles based on previously collected questionnaire data on chronic fatigue syndrome, functional limitations, and healthy aging. In addition, risk factor studies are being planned to merge clinical data with earlier collected risk factor data from questionnaires. Examination data from the subset of National Heart, Lung, and Blood Institute (NHLBI) twins resulted in a number of articles, including the relationship of endogenous sex hormones to coronary heart disease and morphological changes in aging brain structures. The NEO Five-Factor Personality Inventory (a paper-and-pencil self-administered questionnaire) has been fielded for the first time. A push to consolidate the various data holdings of the registry is being made. [ABSTRACT FROM AUTHOR]

The Osaka University Aged Twin Registry (OUATR) is the largest adult twin registry in Japan. Since its establishment in 1974, the OUATR has conducted a number of studies with particular focus on the environmental contribution to physical-cognitive-mental aging, longevity and aging-dependent diseases in later adulthood. The registry consists of 12,000 pairs of Japanese twins born between 1900 and 1935. Two hundred and fifty pairs of twins have undergone comprehensive medical examination to date. Follow-up questionnaires have been mailed out on a regular basis, for the purpose of checking current vital statuses, health conditions, and so forth. The main objective of this longitudinal twin study is to contribute to the prevention of lifestyle-related diseases and the promotion of successful aging. [ABSTRACT FROM AUTHOR]

The Boston University Twin Project (BUTP) is a multi-method, multi-situation, longitudinal study of early child temperament and related behaviors. The first phase of this project focused primarily on activity level and comprised over 300 twin pairs assessed in the home and lab at ages 2 and 3. Subject recruitment, sample characteristics, and study procedures are described. A second phase broadens our focus to the development of multiple temperament dimensions and developmental outcomes in a new cohort of 300 twin pairs to be assessed at 3, 4, and 5 years of age. Recruitment is currently underway. [ABSTRACT FROM AUTHOR]