Chen X, et al. - Researchers undertook this cross-sectional twin study to determine the genetic and environmental influences on the correlations between traits of metabolic syndrome and CKD. Participants were 4,721 complete twin pairs (9,442 European ancestry participants) from the population-based TwinGene project within the Swedish Twin Registry. The identified correlation between metabolic syndrome and eGFR-defined CKD was 0.16. Of this, 51% was explained by genes, whereas 15% was explained by the shared environment and 34% by nonshared environment. The genetic correlation between metabolic syndrome and CKD was 0.29 and the environmental correlation between these was 0.27. The genetic and environmental correlations between abdominal obesity and eGFR were −0.30 and −0.14, respectively. Overall, findings revealed the contribution of both genes and environment to the correlation between metabolic syndrome and eGFR-defined CKD. Especially significant was genetic contribution to the correlation between abdominal obesity and eGFR.