Genetic and environmental factors affecting birth size variation: A pooled individual-based analysis of secular trends and global geographical differences using 26 twin cohorts

Yoshie Yokoyama, Aline Jelenkovic, Yoon-Mi Hur, Reijo Sund, Corrado Fagnani, Maria Antonietta Stazi, Sonia Brescianini, Fuling Ji, Feng Ning, Zengchang Pang, Ariel Knafo-Noam, David Mankuta, Lior Abramson, Esther Rebato, John L Hopper, Tessa L. Cutler, Kimberly J. Saudino, Tracy L. Nelson, Keith E. Whitfield, Robin P CorleyBrooke M. Huibregtse, Catherine A. Derom, Robert F. Vlietinck, Ruth Jf Loos, Clare Llewellyn, Abigail Fisher, Morten Bjerregaard-Andersen, Henning Beck-Nielsen, Morten Sodemann, Robert F Krueger, Matthew McGue, Shandell Pahlen, Meike Bartels, Catherine E M van Beijsterveldt, Gonneke Willemsen, Jennifer R Harris, Ingunn Brandt, Thomas Sevenius Nilsen, Jeffrey M. Craig, Richard Saffery, Lise Dubois, Michel Boivin, Mara Brendgen, Ginette Dionne, Frank Vitaro, Claire Haworth, Robert Plomin, Gombojav Bayasgalan, Danshiitsoodol Narandalai, Finn Rasmussen, Per Tynelius, Adam D. Tarnoki, David L. Tarnoki, Syuichi Ooki, Richard J Rose, Kirsi H Pietiläinen, Thorkild I.A. Sørensen, Dorret Boomsma, Jaakko Kaprio, Karri Silventoinen

Research output: Contribution to journalArticle (Academic Journal)peer-review

13 Citations (Scopus)
183 Downloads (Pure)


Background: The genetic architecture of birth size may differ geographically and over time. We examined differences in the genetic and environmental contributions to birth weight, length, and ponderal index (PI) across geographic-cultural regions (Europe, North-America and Australia, and East-Asia) and across birth cohorts and how gestational age modifies these effects.

Methods: Data from 26 twin cohorts in 16 countries including 57613 monozygotic and dizygotic twin pairs were pooled. Genetic and environmental variations of birth size were estimated using genetic structural equation modeling.

Results: The variance of birth weight and length was predominantly explained by shared environmental factors, whereas the variance of PI was explained both by shared and unique environmental factors. Genetic variance contributing to birth size was small. Adjusting for gestational age decreased the proportions of shared environmental variance and increased the propositions of unique environmental variance. Genetic variance was similar in the geographic-cultural regions, but shared environmental variance was smaller in East-Asia than in Europe and North-America and Australia. The total variance and shared environmental variance of birth length and PI were greater from the birth cohort 1990-1999 onwards compared with the birth cohorts from 1970-1979 to 1980-1989.

Conclusion: The contribution of genetic factors to birth size is smaller than that of shared environmental factors, which is partly explained by gestational age. Shared environmental variances of birth length and PI were greater in the latest birth cohorts and differed also across geographic-cultural regions. Shared environmental factors are important when explaining differences in the variation of birth size globally and over time.
Original languageEnglish
JournalInternational Journal of Epidemiology
Early online date19 May 2018
Publication statusE-pub ahead of print - 19 May 2018


  • Birthweight
  • birth length
  • ponderal index
  • twins
  • genetics
  • pooled studies


Dive into the research topics of 'Genetic and environmental factors affecting birth size variation: A pooled individual-based analysis of secular trends and global geographical differences using 26 twin cohorts'. Together they form a unique fingerprint.

Cite this