Klump, K.L., Burt, S.A., Spanos, A., McGue, M., Iacono, W.G., & Wade, T.D. (2010). Age differences in genetic and environmental influences on weight and shape concerns. International Journal of Eating Disorders, 43(8), 679-688. PMCID: PMC2891330

RESULTS: Genetic influences were modest in preadolescent twins, but significant from early-adolescence through middle adulthood. Shared environmental factors showed the opposite pattern, with the largest shared environmental contributions occurring in the youngest age group. Nonshared environmental effects remained relatively constant across age.
DISCUSSION: Findings highlight the importance of age differences in genetic and environmental influences. Possible mechanisms include gene x environment interactions and biological changes associated with key developmental stages.

Hur, Y.M., Luciano, M., Martin, N.G., Boomsma, D.I., Iacono, W.G., McGue, M., Shin, J.S., Jun, J.K., Ooki, S, van Biejsterveld, C.E.M. & Han, J.Y. (2005) A Comparison of Birth Weight Data from Australia, the Netherlands, the United States, Japan, and South Korea: Are Genetic and Envoronmental Variations Similar in Birthweight Similar in Caucasians and East Asians?  Twin Research and Human Genetics, 8, 638-648.

Klump, K. L., A. Holly, et al. (2000). "Physical similarity and twin resemblance for eating attitudes and behaviors: A test of the equal environments assumption." Behavior Genetics 30(1): 51-58.
Twin studies are based on the assumption that identical and fraternal twin pairs share equally similar environments.  This is usually interpreted to mean that the greater physical similarity of identical twins does not cause them to share more common experiences.  This study made use of MTFS females to test this assumption with respect to eating disordered behaviors and attitudes, with the result that physical similarity was not related to similarity of eating behaviors and attitudes.

Sherman, D. K., W. G. Iacono, & Donnelly, J.M. (1995). "Development and validation of body rating scales for adolescent females." International Journal of Eating Disorders 18(4): 327-33.
This study made use of MTFS 11-year-olds and 17-year-olds to develop practical body rating scales for use in body image research with children and adolescents.