The problem of zygosity misclassification of twins has been paid little attention in Japan. By analyzing maternal reports collected using an internet questionnaire, the author found that around 30% of monozygotic twins were misclassified as dizygotic twins, mainly by obstetricians. On the other hand, the percentage of dizygotic twin pairs misclassified as monozygotic twins was lower. Misclassif...

1 On the history of conjoined twins, see G. M. Gould and W. L. Pyle, Anomalies and Curiosities of Medicine (New York, 1896), 167-89; H. H. Wilder, “Duplicate twins and double monsters,” American Journal of Anatomy 3:4 (1904): 388-472 (which includes a fascinating discussion on the physiological theories of development of conjoined twins); J. Bondeson, Th e Two-Headed Boy and Other Medical Marve...

Highlights from the 15th International Congress of Twin Studies are presented. The congress was held November 16-19, 2014 in Budapest, Hungary. This report is followed by summaries of research addressing the differentiation of MZ co-twins by single nucleotide polymorphisms (SNPs), an unusual error in infant twin-singleton hospital registration, twins with childhood-onset narcolepsy with cataple...

ône-third of population deal with sleep disorders which might be due to social, economic or medical problems. studies on twins have indicated the role of genetic factors in these disorders. monozygotic twins have a very similar hypnogram. â higher prevalence of some sleep disorders is reported in relatives of the patients with these disorders. genes also affect sleep disorders as well as some o...

This paper presents a history of the treatment of conjoined twins. The first mention of this malformation comes from the Neolithic period. Conjoined twins were depicted in mythologies of ancient peoples. The present paper focuses on the theories of formation of Siamese twins and attempts at their separation. Moreover, the history of treatment of conjoined twins in Poland is described.

The twin method assumes that the trait under study is similar in twins and singletons so that the results from twin samples can be generalized to the singleton population. The purpose of the present study was to compare self-concept in twins and singletons matched in parental level of education. The 6 cluster scales of the Piers-Harris Children's Self-Concept Scale (P-H) were administered to 63...

In a large set of twin pairs, we compared twins born after IVF to naturally conceived twins with respect to birth characteristics, growth, attainment of motor milestones, and emotional and behavioral problems. Twin families were registered with the Netherlands Twin Register. We included 1534 dizygotic (DZ) twins born after IVF, 5315 naturally conceived (NC) DZ twins, and 1504 control NC DZ twin...

OBJECTIVE Twins in Africa may be at increased risk of metabolic disorders due to strained conditions in utero, including high exposure to infections. We studied metabolic syndrome (MS) and diabetes mellitus (DM) among young twins and singletons in Guinea-Bissau. RESEARCH DESIGN AND METHODS The study was cross-sectional and occurred from October 2009 until August 2011 at the Bandim Health Proj...

Among 1195 twins born in the Collaborative Perinatal Project, for whom information was available, 219 (18.33%) were found to have malformations, 179 (14.98%) single and 40 (3.35%) multiple. The frequency of malformations and malformed individuals was significantly higher in twins than in singletons from the same population but the difference was entirely contributed by MZ twins. This held true ...

BACKGROUND Although the clinical importance of chorionicity in twin pregnancies has been studied widely, the significance of perinatal determination of zygosity using molecular genetic analyses remains controversial. The purpose of this study was to determine the frequency and clinical significance of twin gestations according to zygosity and chorionicity in a Korean population. METHODS We en...