The twin children who survived the Holocaust and the horrific medical experiments conducted by Nazi doctors are sometimes overlooked in the relevant literature. This topic and more were discussed as part of an annual conference hosted by students from Yeshiva University's Medical Ethics Society in October 2012. A selective summary of this meeting is followed by summaries of recent twin studies concerning genetic influences on twinning, in vitro fertilization versus spontaneous twin pregnancies, gender identity disorder, and royal support for twin registries. Several human interest stories are also worth noting. They include identical twin school principals, twin loss at Sandy Hook Elementary School, timely twin documentaries, new twin and twin-like reunions, and the passing of two prominent twins.

Fetal movements and fetal heart rate (FHR) are well-established markers of fetal well-being and maturation of the fetal central nervous system. The purpose of this paper is to review and discuss the available knowledge on fetal movements and heart rate patterns in twin pregnancies. There is some evidence for an association or similarity in fetal movement incidences or FHR patterns between both members of twin pairs. However, the temporal occurrence of these patterns seems to be for the most part asynchronous, especially when stricter criteria are used to define synchrony. The available data suggest that fetal behavior is largely independent of sex combination, fetal position, and presentation. Conversely, chorionicity appears to have some influence on fetal behavior, mainly before 30 weeks of gestation. There is preliminary evidence for the continuity of inter-individual differences in fetal activity and FHR patterns over pregnancy. Comparisons between studies are limited by large methodological differences and absence of uniform concepts and definitions. Future studies with high methodological quality are needed to provide a more comprehensive knowledge of normal fetal behavior in twin pregnancy.

Over the last 60 years, the resources and the research in the Danish Twin Registry (DTR) have periodically been summarized. Here, we give a short overview of the DTR and a more comprehensive description of new developments in the twenty-first century. First, we outline our experience over the last decade of combining questionnaire and survey data with national demographic, social, and health registers in Statistics Denmark. Second, we describe our most recent data collection effort, which was conducted during the period 2008–2011 and included both in-person assessments of 14,000+ twins born 1931–1969 and sampling of biological material, hereby expanding and consolidating the DTR biobank. Third, two examples of intensively studied twin cohorts are given. The new developments in the DTR in the last decade have facilitated the ongoing research and laid the groundwork for new research directions.

Background: Twin pregnancies are at increased physiological and psychosocial risks. Objective: To investigate the prevalence of major depression in twin pregnancies and correlate with stress and social support. Method: The study included 51 pregnant women under specialized prenatal care who were evaluated by a Portuguese version of the semi-structured questionnaire Primary Care Evaluation of Mental Disorders (PRIME-MD) for Major Depression, and the Prenatal Psychosocial Profile (PPP) for evaluation of stress and social support. Results: Major depression was found in 33.3% of pregnant women, and prevailing symptoms were fatigue or loss of energy (100%), insomnia or hypersomnia (82.4%), changes in appetite (82.4%), decreased interest in daily activities (82.4%), and psychomotor agitation or retardation (82.4%). Among pregnant women who were diagnosed depressive, 76.5% also had a high level of stress and 47.1% complained about lack of social support. Statistical significance was found when correlating depression with perception of negative aspects of having twins and belief in significant body changes during pregnancy (p = .005 and .03, respectively). Marital status, occupation, and pregnancy planning were not significantly associated with the diagnosis of depression. Conclusion: Major depression occurs in one-third of pregnant women expecting twins and is associated with higher levels of stress and lack of social support. A multidisciplinary approach in these cases is fundamental to minimize further risks and complications.

The population-based Northern Survey of Twin and Multiple Pregnancy (NorSTAMP, formerly the Multiple Pregnancy Register) has collected data since 1998 on all multiple pregnancies in North of England (UK) from the earliest point of ascertainment in pregnancy. This paper updates recent developments to the NorSTAMP and presents some early mortality data from the first 10 years of data collection (1998–2007). Since 2005, mothers have been asked to give explicit consent for their identifiable data to be held by the survey, in line with changing guidance and legal frameworks for identifiable data. In 2009, regional standards of care for multiple pregnancies were developed, agreed, and disseminated. During 1998–2007, 4,865 twin maternities (pregnancies with at least one live birth or stillbirth) were registered, with an average twinning rate of 14.9 per 1,000 maternities. The overall stillbirth and neonatal mortality rates in twins were 18.0/1,000 births and 23.0/1,000 live births respectively. Stillbirth and neonatal mortality rates were significantly higher in monochorionic than dichorionic twins: 44.4 versus 12.2 per 1,000 births (relative risk [RR] 3.6, 95% Confidence Intervals [CI] 2.6–5.1), and 32.4 versus 21.4 per 1,000 live births (RR 1.5, 95% CI 1.04–2.2) respectively. There was no significant improvement during this period in either stillbirth or neonatal mortality rates in either chorionicity group. This population-based survey is an important source of data on multiple pregnancies, which allows monitoring of trends in multiple birth rates and pregnancy losses, providing essential information to support improvements in clinical care and for epidemiological research.

This study aimed to explore if natural dizygotic (DZ) twinning is associated with earlier menopause and lower anti-Mullerian hormone (AMH) values. We investigated if advanced biological reproductive aging, which can be responsible for the multiple follicle growth in familial twinning, is similar to mechanisms that occur in normal ovarian aging, reflected by earlier menopause in mothers of DZ twins and lower levels of AMH. A total of 16 mothers of DZ twins enrolled with the Netherlands Twin Register (average age at first assessment: 35.9 ± 3.0 years) and 14 control mothers (35.1 ± 3 years) took part in a prospective study. Fifteen years after entry into the study, which included follicle-stimulating hormone (FSH) assessment, AMH was measured in stored serum samples and menopause status was evaluated. Average AMH levels were not significantly different between DZ twin mothers and controls (2.1 ± 2.4 μg/L vs. 1.9 ± 1.9 μg/L). Among the 16 mothers of twins, 7 had an elevated (FSH) value over 10 U/L at first assessment. Their AMH levels were lower than the nine twin mothers with normal FSH values: 0.6 ± 0.4 versus 3.4 ± 2.6 μg/L (p = .01). Of the mothers of twins, eight mothers had entered menopause at the second assessment compared with only one control mother (p = .07). Thus, slightly more DZ mothers were in menopause than the control mothers, although this difference was not significant. The subgroup of DZ twin mothers who had an increased FSH concentration 15 years ago had a limited ovarian reserve as reflected by lower AMH levels. These data indicate that advanced ovarian aging can be a feature in familial DZ twinning, particularly with elevated early follicular phase FSH.

The infant mortality rate (IMR) among single and twin births from 1999 to 2008 was analyzed using Japanese Vital Statistics. The IMR was 5.3-fold higher in twins than in singletons in 1999 and decreased to 3.9-fold in 2008. The reduced risk of infant mortality in twins relative to singletons may be related, partially, to survival rates, which improved after fetoscopic laser photocoagulation for twin — twin transfusion syndrome. The proportion of neonatal deaths among total infant deaths was 54% for singletons and 74% for twins. Thus, intensive care of single and twin births may be very important during the first month of life to reduce the IMR. The IMR decreased as gestational age (GA) rose in singletons, whereas the IMR in twins decreased as GA rose until 37 weeks and increased thereafter. The IMR was significantly higher in twins than in singletons from the shortest GA (<24 weeks) to 28 weeks as well as ≥38 weeks, whereas the IMR was significantly higher in singletons than in twins from 30 to 36 weeks. As for maternal age, the early neonatal and neonatal mortality rates as well as the IMR in singletons were significantly higher in the youngest maternal age group than in the oldest one, whereas the opposite result was obtained in twins. The lowest IMR in singletons was 1.1 per 1,000 live births for ≥38 weeks of gestation and heaviest birth weight (≥2,000 g), while the lowest IMR in twins was 1.8 at 37 weeks and ≥2,000 g.

The Twins Early Development Study (TEDS) is a large longitudinal sample of twins born in England and Wales between 1994 and 1996. The focus of TEDS has been on cognitive and behavioral development, including difficulties in the context of normal development. TEDS began when multiple births were identified from birth records and the families were invited to take part in the study; 16,810 pairs of twins were originally enrolled in TEDS. More than 10,000 of these twin pairs remain enrolled in the study to date. DNA has been collected for more than 7,000 pairs, and genome-wide genotyping data for two million DNA markers are available for 3,500 individuals. The TEDS families have taken part in studies when the twins were aged 2, 3, 4, 7, 8, 9, 10, 12, 14, and 16 years of age. Data collection is currently underway to assess the adult destinations of the twins as they move from school to university and the workplace. Between January 2012 and December 2014, all of the TEDS twins will turn 18, and the study will transition to an adult sample. TEDS represents an outstanding resource for investigating the developmental effects of genes and environments on complex quantitative traits from childhood to young adulthood and beyond.

In 2013, the Education Committee of the Human Genetics Society of Australasia (HGSA) established the DNA Day Essay Contest in Australia and New Zealand. The contest was first established by the American Society of Human Genetics in 2005 and the HGSA DNA Day Essay Contest is adapted from this contest via a collaborative partnership. The aim of the contest is to engage high school students with important concepts in genetics through literature research and reflection. As 2013 marks the 60th anniversary of the discovery of the double helix of DNA by James Watson and Francis Crick and the 10th anniversary of the first sequencing of the human genome, the essay topic was to choose either of these breakthroughs and explain its broader impact on biotechnology, human health and disease, or our understanding of basic genetics, such as genetic variation or gene expression. The contest attracted 87 entrants in 2013, with the winning essay authored by Patrick Yates, a Year 12 student from Melbourne High School. Further details about the contest including the names and schools of the other finalists can be found at http://www.hgsa-essay.net.au/. The Education Committee would like to thank all the 2013 applicants and encourage students to enter in 2014.

Joanne M. Lind, BSc, PhD

Chair, HGSA Education Committee

The Russian School Twin Registry (RSTR) was established in 2012, supported by a grant from the Government of the Russian Federation. The main aim of the registry is to contribute to Progress in Education through Gene-Environment Studies (PROGRESS). The formation of the registry is ongoing and it is expected that most schools in the Russian Federation (approximately 50,000 schools) will contribute data to the registry. With a total of 13.7 million students in Grades 1–11 (ages 7–18), the potential number of twin pairs exceeds 100,000. Apart from the large sample size and its representative nature, the RSTR has one unique feature: in collaboration with the International Advisory Committee to the Registry, genetically sensitive cross-cultural investigations are planned, aided by the use of the common assessment instruments. Other strengths of the registry include the assessment of a large sample of non-twin school children, including those studying in the same classes as the twins in the registry. It is hoped that the RSTR will provide an important research platform for national and international educationally relevant research.

A foundation for studying multiple myeloma, launched by a monozygotic twin, is described. Twin studies of that disease are also examined. A summary of selected research studies and news events follows, with specific reference to a new critique of twin research, sexual attraction in separated opposite-sex twins, twinning rates following assisted reproductive technology and family histories of multiple implantation. Human interest topics cover a gathering of researchers from the Minnesota Study of Twins Reared Apart, morning sickness and twin pregnancy, sexuality in conjoined twins, a famous hidden twin, and a film about switched at birth babies.

Switched-at-birth twins from Las Palmas, Gran Canaria in Spain drew international attention in May 2008 following news reports of their unexpected reunion. I visited Las Palmas in September 2009 to research this case and presented the findings in Segal and Blandón-Gitlin (Twin Research and Human Genetics, Vol. 13, 2010, pp. 115–119) and in a book, Someone Else's Twin: The True Story of Babies Switched at Birth (Segal, Prometheus Books, Amherst, New York, 2011). I traveled again to Las Palmas in November 2012 to meet with the twins, their families, and their attorneys and have updated my findings in this article. Next, new twin research on Parkinson's disease discordance, neonatal surgery, double embryo transfer in a cynomolgus monkey, and a convention conundrum are presented. Media highlights concerning twin inventors, basketball players, rappers, designers, musicians, and birth intervals are also summarized.