Table 1.
Subject characteristics of DZ and MZ Chinese adolescent twins (n = 226)a
| DZ and MZ twins | DZ twins | MZ twins | |
|---|---|---|---|
| n | 226 | 107 | 119 |
| Age (yr) | 16.4 (1.5) | 16.5 (1.5) | 16.4 (1.5) |
| Height (cm) | 157.8 (7.5) | 158.6 (7.3) | 157.1 (7.6) |
| Weight (kg) | 48.6 (6.4) | 49.0 (6.0) | 48.1 (6.7) |
| Body mass index (kg/m2) | 19.5 (2.0) | 19.5 (2.0) | 19.5 (2.1) |
| Gender (% females) | 52.7 | 47.7 | 57.1 |
| Tanner (% stage III) | 53.1 | 53.3 | 52.9 |
| Season (% summer)b | 56.2 | 53.3 | 58.8 |
| Student (% students)c | 76.6 | 70.1d | 82.4 |
| Physical activity (IPAQ), n (%) | |||
| Low | 117 (52.2) | 51 (48.5) | 66 (55.5) |
| Moderate | 61 (27.2) | 26 (24.8) | 35 (29.4) |
| High | 46 (20.5) | 28 (26.7) | 18 (15.1) |
Data represent mean (sd) unless otherwise described.
a
Sample restricted to Tanner stages III and IV; five DZ pairs had only one twin; three MZ pairs had only one twin.
b
Serum collected in January and February = non-summer; and serum collected in July, August, and September = summer.
c
Non-students consisted of farmers, laborers, professional, office clerk, waiter, homemaker, and other.
d
DZ twins significantly different from MZ twins, P = 0.03.