Differing socioeconomic positions in adult life are associated with differences in the health of twins raised together.
Krieger, N., Chen, J. T., Coull, B. A., & Selby, J. V. (2005). Lifetime socioeconomic position and twins’ health: An analysis of 308 pairs of United States women twins. PLoS Medicine, 2(7), 0645–0653. https://doi.org/10.1371/journal.pmed.0020162