Gene Discovery Using Twins.

One of Nick's key early achievements at QIMR was to establish a twin study on melanoma risk factors. The Brisbane Twin Nevus Study (BTNS) had an initial focus on nevus (mole) count in adolescents but, reflecting Nick's broad interests, expanded in scope enormously over the decades. In the skin cancer arena, BTNS was essential to genetic discoveries in melanoma, eye color and pigmentation. Later studies amassed data on thousands of phenotypes, ranging from molecular phenotypes such as gene expression to studies where gene mapping findings in adolescents turned out to have translational potential in late-onset diseases. Nick's twin data have formed the basis for an enormous range of discoveries, with Nick and his colleagues continuing to capitalize on these data.

Twins Reared Apart: Zygotic Division After Artificial Insemination/Twin Research Reviews: Selective Resuscitation of Premature Twins; Scientist Jailed for Editing Twins' Genes; Sexual Arousal Patterns in MZ Twins Discordant for Sexual Orientation; MZ Twins With Jejuno-Ileal Atresia/Media Reports: Twin Girls' Search for a Bone Marrow Donor; Puppy with a Possible Parasitic Twin; Twins in Silicon Valley; Surgical Separation of Craniopagus Twins; Twin-Based New Yorker Magazine Cartoon; Twin Tragedies.

This article opens with the brief life histories of reared-apart monozygotic (MZ) male twins. A New York City program that helped childless couples conceive via artificial insemination from the 1930s to the 1950s is examined as it related to these twins. The frequency with which pregnancies following assisted reproductive technology resulted in MZ twin pairs is also provided. Next, summaries of twin research concerning selective resuscitation, gene editing, sexual arousal and jejuno-ileal atresia are presented. The article ends with media reports of twin girls' efforts to find a bone marrow donor for their father, possible parasitic twinning in a puppy, identical female twins' business venture, the surgical separation of craniopagus twins, a twin-themed magazine cartoon and tragic events involving identical male twins.

Contributions of Nicholas Martin to Gambling Disorder Research.

Professor Nicholas G. Martin, from QIMR Berghofer Medical Research Institute in Brisbane, Australia, is a world leader in the effort to understand the genetic architecture underlying disordered gambling. This article pays tribute to Nick and his almost two decades of gambling research, highlighting his many strengths, ranging from the use of ingenious recruitment approaches, twin study methods, genomewide association studies, to facilitating international collaborations.

[A monstrous birth in the Middle Ages: the "Salernitan brother"]. / Une naissance monstrueuse au Moyen Age: le "frère de Salerne".

Gilles de Corbeil (XIIth century) reports the strange medical case of the "Salernitan brother", a monster born together with a normal child. This disorder is said to be typical of Salernitan women. The phenomenon which is still commented on by physicians in the following centuries is rather difficult to explain for it seems to depend on both scholarly medicine and popular beliefs.

1954.

1954 marked the most important year for modern transplantation. It represented the date in which the first successful live kidney transplant was performed by the devoted group of Joseph Murray, Hartwell Harrison, and their Peter Bent Brigham associates in Boston. Intense preparation and careful analysis was required for a long time to arrive at the resounding success manifested in the case of the Herrick twin brothers. Years later, only the discovery of chemical immunosuppression such as azathioprine and the use of radiation therapy permitted occasional good results in kidney transplantation. Great contributors of this period included Elion and Hitchings, Calne and Zukowski, Woodruff, Goodwin, and many others. In a few more years, the use of steroids and an antilymphocyte preparation by the committed team of Tom Starzl from Colorado improved the opportunities for patient outcome. The latter part of the 1960s witnessed the maturation of the Minnesota program with the arrival of John Najarian from California. The 1970s introduced different morbidity and mortality associated with immunosuppressive treatment, and required adjustments in patient management were necessary. New advances were to come in years ahead.

The first "classical" twin study? Analysis of refractive error using monozygotic and dizygotic twins published in 1922.

The first classical twin studies, recognizing the potential of comparing findings in identical twins, have previously been reported to be those by Siemens and by Merriman, both published in 1924. However, we would like to bring to attention a study performed by Walter Jablonski, 2 years earlier (1922), investigating the contribution of heredity to refraction in human eyes. Jablonski examined the eyes of 52 twin pairs and by comparing the size of within-pair differences between identical and nonidentical twins was able to infer the heritability of a trait. Therefore, this is likely to be the first reported classical twin study.

The first successful separation of conjoined twins (1689).

Reports on the first successful separation of conjoined twins in 1689 and especially the publication of this achievement, as late as 1752, in the Helvetisch-vernünftiche Wehe-Mutter by Johannes Fatio are discussed in this paper with the intention to correct several historical inaccuracies.

Epilepsy in twins: insights from unique historical data of William Lennox.

OBJECTIVE: To classify the Lennox twin pairs according to modern epilepsy classifications, use the classic twin model to identify which epilepsy syndromes have an inherited component, search for evidence of syndrome-specific genes, and compare concordances from Lennox's series with a contemporary Australian series. METHODS: Following review of Lennox's original files describing twins with seizures from 1934 through 1958, the International League Against Epilepsy classifications of seizures and epileptic syndromes were applied to 169 pairs. Monozygous (MZ) and dizygous (DZ) pairs were subdivided into epilepsy syndromes and casewise concordances estimated. RESULTS: The authors excluded 26 pairs, with 71 MZ and 72 DZ pairs remaining. Seizure analysis demonstrated strong parallels between contemporary seizure classification and Lennox's terminology. Epilepsy syndrome diagnoses were made in 75%. The MZ and DZ casewise concordance estimates gave strong evidence for a major genetic influence in idiopathic generalized epilepsies (0.80 versus 0.00; n = 23). High MZ casewise concordances also supported a genetic etiology in symptomatic generalized epilepsies and febrile seizures. The pairs who were concordant for seizures usually had the same syndromic diagnoses in both twins (86% in MZ, 60% in DZ), suggesting syndrome-specific genes. Apart from partial epilepsies, the MZ casewise concordances were similar to those derived from Australian twin data. CONCLUSIONS: The authors were able to apply contemporary classifications to Lennox's twins. The data confirm genetic bases for common generalized epilepsies as well as febrile seizures and provide further support for syndrome-specific genes. Finally, comparable results to our Australian series were obtained, verifying the value of twin studies.

Colpocephaly in identical twins.

Colpocephaly is congenital disproportionately enlarged occipital horns of the lateral ventricles. It is easily recognized on computed tomography, magnetic resonance imaging or cerebral ultrasonography. The first report of colpocephaly in identical twins is presented. This is also the first reported instance of above normal intelligence occurring in conjunction with colpocephaly. The associated anomalies found as mirror images in these twins imply a genetic basis for their colpocephaly.