A trend toward greater body size in dizygotic (DZ) than in monozygotic (MZ) twins has been suggested by some but not all studies, and this difference may also vary by age. We analyzed zygosity differences in mean values and variances of height and body mass index (BMI) among male and female twins from infancy to old age. Data were derived from an international database of 54 twin cohorts participating in the COllaborative project of Development of Anthropometrical measures in Twins (CODATwins), and included 842,951 height and BMI measurements from twins aged 1 to 102 years. The results showed that DZ twins were consistently taller than MZ twins, with differences of up to 2.0 cm in childhood and adolescence and up to 0.9 cm in adulthood. Similarly, a greater mean BMI of up to 0.3 kg/m2 in childhood and adolescence and up to 0.2 kg/m2 in adulthood was observed in DZ twins, although the pattern was less consistent. DZ twins presented up to 1.7% greater height and 1.9% greater BMI than MZ twins; these percentage differences were largest in middle and late childhood and decreased with age in both sexes. The variance of height was similar in MZ and DZ twins at most ages. In contrast, the variance of BMI was significantly higher in DZ than in MZ twins, particularly in childhood. In conclusion, DZ twins were generally taller and had greater BMI than MZ twins, but the differences decreased with age in both sexes.
Jelenkovic A, Yokoyama Y, Sund R, Honda C, Bogl LH, Aaltonen S, Ji F, Ning F, Pang Z, Ordoñana JR, Sánchez-Romera JF, Colodro-Conde L, Burt SA, Klump KL, Medland SE, Montgomery GW, Kandler C, McAdams TA, Eley TC, Gregory AM, Saudino KJ, Dubois L, Boivin M, Tarnoki AD, Tarnoki DL, Haworth CM, Plomin R, Öncel SY, Aliev F, Stazi MA, Fagnani C, D’Ippolito C, Craig JM, Saffery R, Siribaddana SH, Hotopf M, Sumathipala A, Rijsdijk F, Spector T, Mangino M, Lachance G, Gatz M, Butler DA, Bayasgalan G, Narandalai D, Freitas DL, Maia JA, Harden KP, Tucker-Drob EM, Kim B, Chong Y, Hong C, Shin HJ, Christensen K, Skytthe A, Kyvik KO, Derom CA, Vlietinck RF, Loos RJ, Cozen W, Hwang AE, Mack TM, He M, Ding X, Chang B, Silberg JL, Eaves LJ, Maes HH, Cutler TL, Hopper JL, Aujard K, Magnusson PK, Pedersen NL, Aslan AK, Song YM, Yang S, Lee K, Baker LA, Tuvblad C, Bjerregaard-Andersen M, Beck-Nielsen H, Sodemann M, Heikkilä K, Tan Q, Zhang D, Swan GE, Krasnow R, Jang KL, Knafo-Noam A, Mankuta D, Abramson L, Lichtenstein P, Krueger RF, McGue M, Pahlen S, Tynelius P, Duncan GE, Buchwald D, Corley RP, Huibregtse BM, Nelson TL, Whitfield KE, Franz CE, Kremen WS, Lyons MJ, Ooki S, Brandt I, Nilsen TS, Inui F, Watanabe M, Bartels M, van Beijsterveldt TC, Wardle J, Llewellyn CH, Fisher A, Rebato E, Martin NG, Iwatani Y, Hayakawa K, Sung J, Harris JR, Willemsen G, Busjahn A, Goldberg JH, Rasmussen F, Hur YM, Boomsma DI, Sørensen TI, Kaprio J, Silventoinen K. Zygosity Differences in Height and Body Mass Index of Twins From Infancy to Old Age: A Study of the CODATwins Project. Twin Res Hum Genet. 2015 Oct;18(5):557-70. PMC4605819.