Dandy-Walker syndrome in monozygotic twins is reported. The twins reported, presented with delayed development, big head and dysmorphic features. In addition, there were significant cafe-au-lait spots on the trunk and other minor features consistent with the diagnosis of neurofibromatosis. To the best of our knowledge, Dandy-Walker syndrome in combination with neurofibromatosis in monozygotic t...

OBJECTIVE To estimate fetal fraction (FF) in monozygotic and dizygotic twin pregnancies. METHODS Maternal plasma samples were obtained from 35 monochorionic twin pregnancies with male fetuses (monozygotic) and 35 dichorionic pregnancies discordant for fetal sex (dizygotic) at 11-13 weeks' gestation. Cell-free DNA was extracted and chromosome-selective sequencing with digital analysis of selec...

Recent studies report a high incidence of monozygotic twinning in Beckwith-Wiedemann syndrome. A phenotypical discordance in monozygotic twins is rare. Twinning and Beckwith-Wiedemann syndrome show higher incidence in children born after assisted reproductive techniques. We report on the first observation of esophageal atresia and Beckwith-Wiedemann syndrome in one of the naturally conceived di...

OBJECTIVE To examine brain-behavior relationships in attention deficit hyperactivity disorder (ADHD), the authors obtained magnetic resonance imaging (MRI) scans of monozygotic twins discordant for ADHD. METHOD National recruitment was followed by in-person assessment. MRI scans were measured algorithmically for nine pairs of monozygotic twins discordant for ADHD. RESULTS The affected twins...

Intestinal atresia in both twins from the same pregnancy is very rare. Only seven pairs of twins have been described. The authors report on two cases of monozygotic twins with different types of intestinal atresia and clinical evolution. Both pairs of observed twins turned out to be concordant for the presence of intestinal malformations and for the absence of other linked malformations; nevert...

A pair of male monozygotic twins discordant for Rubinstein-Taybi syndrome is reported. Monozygosity of the twins was established using blood grouping, typing of serum proteins, isozymes, HLA, and chromosomal heteromorphisms. The twins are the first twin pair discordant for the syndrome in which monozygosity has been firmly established. The pathogenesis of the syndrome is discussed in relation t...

In the cardiac clinic of the Hospital for Sick Children, Toronto, a 6-year-old girl with an auricular septal defect was found to have a monozygotic twin in whom the heart was normal. Instances of congenital heart disease in both of monozygotic twins have been reported by several authors. Smith (1929) observed a patent ductus arteriosus in both of twin boys of similar general appearance, size, a...

OBJECTIVE To study the influence of zygosity on the metabolic variables involved in the pathophysiology of type 2 diabetes. DESIGN Population based cross sectional study. SETTING Odense University Hospital, Denmark. PARTICIPANTS 125 monozygotic twin pairs and 178 dizygotic twin pairs of the same sex born between 1921 and 1940. MAIN OUTCOME MEASURES Clinical characteristics of monozygoti...

We investigated 21 pairs of twins for zygosity and idiopathic scoliosis. DNA fingerprinting confirmed that 13 pairs were monozygotic and eight were dizygotic. There was concordance for idiopathic scoliosis in 92.3% of monozygotic and 62.5% of dizygotic twins. Of the 12 pairs of monozygotic twins concordant for idiopathic scoliosis, six showed discordant curve patterns but eight had differences ...

The factors controlling immunoglobulin (Ig) gene repertoire formation are poorly understood. Studies on monozygotic twins have helped discern the contributions of genetic versus environmental factors on expressed traits. In the present experiments, we applied a novel anchored PCR-ELISA system to compare the heavy chain V gene (V H ) subgroup repertoires of m and g expressing B lymphocytes from ...