Suchergebnisse

AbstractThe University of São Paulo Twin Panel (Painel USP de Gêmeos), based at the Institute of Psychology of the University of São Paulo, started formally in 2017. Our registry is new, but in only two years of formal existence, it comprises a volunteer sample of 4826 registered individuals (98% twins and 2% higher-order multiples), recruited at the University of São Paulo and by social media campaigns. Our main aim is to conduct and promote research with twins on psychological processes and behavior. The University of São Paulo is the largest higher education and research institution in South America, and the Painel USP de Gêmeos has great potential for fostering research on twin-related issues from a psychological perspective in Brazil and South America.

AbstractNew legislation giving parents a voice in deciding their twins' school placement situation (same or separate classrooms) was passed in Minnesota in spring 2005. Since then, parents in several other states have started petitions and lobbying efforts to persuade their senators and representatives to follow suit. A review and update of these exciting developments is presented, followed by a report from the recently established Asian Society for Twin Studies. Reviews of two new twin studies — bases of political attitudes and age effects on dizygotic twinning — are presented. The uniquely informative lives of several twin pairs are also documented.

Findings from twin studies of musical interests and talent are reviewed as a backdrop to the lives and careers of twin jazz musicians, Peter and Will Anderson. The Anderson twins exemplify many aspects of twin research, namely their matched musical abilities, shared musical interests, and common career. This overview is followed by reviews of studies and case reports of bereavement in families who have lost a preterm multiple birth infant, the conception of conjoined twins following in vitro fertilization (IVF), depression in fathers of twins, and twin-to-twin transfusion incidence in monochorionic-diamniotic IVF twin pairs. Twins highlighted in the media include high-achieving identical female twins with nearly identical academic standing, tennis star Roger Federer's two sets of identical twin children, surgical separation of craniopagus conjoined twins, and the rare delivery of twins to a 23-year-old giant panda.

The interrelatedness between twin research and the arts is explored via a new play about a famous case. In the 1960s, identical twin David Bruce Reimer was accidentally castrated as an infant during circumcision to correct a urinary problem. The decision to raise him as a girl, and the consequences of that decision, are explored in the new theatrical production of Boy. Other examples of the arts mirroring science, and vice versa, are described. Next, brief reviews and summaries of twin research on sexual orientation, 1860s' knowledge of placental arrangements and twinning mechanisms, and genes underlying multiple birth conception and fertility related measures are provided. This article concludes with a look at twins on college campuses and the identification of individuals by their brain waves. A correction and clarification regarding my article on the Brazilian Twin Registry in the last issue of THG (Segal, 2016) is also provided.

The establishment of the Brazilian Twin Registry for the study of genetic, social, and cultural influences on behavior is one of eleven newly funded projects in the Department of Psychology at the University of São Paulo. These 11 interrelated projects form the core of the university's Center for Applied Research on Well-Being and Human Behavior. An overview of the planned twin research and activities to date is presented. Next, two recent twin studies are reviewed, one on the relationship between alcohol consumption and mortality, and the other on factors affecting maximal oxygen uptake. Twins cited in the media include the first identified superfecundated twins in Vietnam, adolescent twin relations, twins and triplets who work together, monozygotic twins with different skin tones and a co-twin control study that addresses the effects of space travel.

Cervical cancer is the third most common cancer in women worldwide. Persistent infection with an oncogenic human papillomavirus (HPV) is necessary, but not sufficient, for its development. Over many years, only a small proportion of women with chronic HPV infection progress to develop disease. The role of host genes and environmental factors in the pathogenesis of, or predisposition to, cervical cancer is still unclear. We conducted a systematic review of published literature in MEDLINE–PubMed to identify studies of cervical cancer susceptibility that used a twin study design. We used standard MeSH terms (controlled vocabulary) as well as specific free-text terms and combinations of terms related to cervical cancer, with no restriction on publication date. We performed a full text review to ensure the identified articles met our inclusion criteria and, if so, extracted information on demographics, sample size, study definitions, and key statistical findings. Of the 285 articles identified, three utilized a classical twin design and reported results specific to cervical cancer. The studies were based on cancer registry data from Scandinavia, with sample sizes ranging from 312 to 710 twin pairs. The findings from one study were consistent with a genetic mechanism for the causation of carcinoma in situ. Future research studies using the strength of the classic twin design, together with incorporation of HPV DNA status, are indicated to determine whether there is a potential role for genetic factors in the development of cervical cancer or high-grade cervical dysplasia from chronic oncogenic HPV infection.

The lives of the illustrious monozygotic (MZ) twins, Victor A. and Vincent L. McKusick, are described. Victor earned the distinction as the 'Father of Medical Genetics', while Vincent was a legendary Chief Justice of the Maine Supreme Court. This dual biographical account is followed by two timely reports of twinning rates, a study of MZ twin discordance for Russell–Silver Syndrome (RSS) and a study of twins' language skills. Twin stories in the news include babies born to identical twin couples, a case of switched identity, the death of Princess Ashraf (Twin) and a new mother of twins who is also Yahoo's CEO.

Ten classic works in twin research are described. These volumes are rich in data, interpretation, and impact, and contain life history material that adds depth and dimension to the quantitative findings. Next, research on social relationships in older twins, superfecundated twinning in chimpanzees; effects of embryo transfer on conjoined twinning and the reduced frequency of in vitro multiples is reviewed. Finally, there has been considerable public interest surrounding the first identical twin renal transplant, an identical triplet wedding; identical twin boxers, a twin living in space, and a politically active twin pair.