Journal article

Why Accurate Knowledge of Zygosity is Important to Twins

Tessa L Cutler, Kate Murphy, John L Hopper, Louise A Keogh, Yun Dai, Jeffrey M Craig

Twin Research and Human Genetics | CAMBRIDGE UNIV PRESS | Published : 2015


All same-sex dizygotic (DZ) twins and approximately one-third of monozygotic (MZ) twin pairs have separate placentas, making it impossible to use the number of placentas to determine zygosity. Zygosity determination is further complicated because incorrect assumptions are often made, such as that only DZ pairs have two placentas and that all MZ pairs are phenotypically identical. These assumptions, by twins, their families and health professionals, along with the lack of universal zygosity testing for same-sex twins, has led to confusion within the twin community, yet little research has been conducted with twins about their understanding and assumptions about zygosity. We aimed to explore a..

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Awarded by Centre of Research Excellence from National Health & Medical Research Council

Funding Acknowledgements

We thank all twins and parents of twins who participated in this study. We thank Justine and Elise Marum for their helpful suggestions. We acknowledge Jane Loke, Boris Novakovic, and Anna Czajko for technical assistance during data collection. This research was facilitated through access to the Australian Twin Registry, a national resource supported by a Centre of Research Excellence (ID 1079102) from the National Health & Medical Research Council. JMC is supported by grants from the national Institutes of Health and the Australian National Health and Medical Research Council and by the Murdoch Childrens Research Institute.