The CODATwins Project: The Current Status and Recent Findings of COllaborative Project of Development of Anthropometrical Measures in Twins.
Level 3 - non-randomized controlled study
Pooled individual participant data analysis of 54 observational twin cohorts across 24 countries.
PubMed 31364586 · doi:10.1017/thg.2019.35
What was done
The CODATwins project pooled individual-level phenotype data from 54 twin cohorts across 24 countries to analyze genetic and environmental variation in height, body mass index (BMI), and size at birth. The dataset combined longitudinal and cross-sectional records of height, weight, zygosity, birth weight, birth length, smoking behavior, and education to perform genetic epidemiological and within-family analyses across ages, birth cohorts, and geographic regions.
What was found
The database pooled 489,981 twin individuals (228,635 complete twin pairs) with a total of 1,049,785 height and weight observations. The authors reported that heritability estimates of height and BMI changed systematically from infancy to old age. Differences in heritability estimates across cultural-geographic regions, measurement times, and birth cohorts were minor. The abstract reported no specific numerical values or effect sizes for heritability estimates or covariate associations.
Why it matters
This massive international collaboration demonstrates that the genetic architecture underlying height and BMI shifts across the human lifespan while remaining broadly consistent across historical periods and global regions.
Limits
The abstract reports summary trends without quantitative estimates, confidence intervals, or p-values. As an observational pooling of disparate twin cohorts, findings may be subject to variable measurement protocols, unmeasured environmental confounders, and varying availability of covariates across participating cohorts.
Cited by
- contradicts Research, including work by Dr. Zachary Knight, indicates that body weight and body fat are more genetically predetermined than height.