Heritability Analysis Of Body Size Indices For Adolescent Twins

Objective To investigate the impact of inheritance on height, weight, body mass index (BMI), waist circumference and waist-hip ratio (WHR) in adolescent by the classic twin design.Methods 375 pairs of twins aged 11-19 years old were recruited from the Qingdao Twin Registry. Height, weight, BMI, waist circumference and WHR were measured. Zygosity in all same-sex twin pairs was determined by 16 polymorphic markers. SPSS and Mx software package were used as the statistical methods to build structural equation models. Heritability was assessed by structural equation models.Results 362 pair's effective data of adolescent twins'Height, weight, BMI were collected. 327 pair's effective data of adolescent twins' waist circumference and WHR were chosen. By fitting and analyzing of the data converted, the ACE model combining additive genetic and unique environmental factors was fit for height, waist circumference and WHR and AE model was fit for weight and BMI. After adjusting sex and age, the heritability of height, weight, BMI, waist circumference and WHR were 66%,84%,75 %,8%,53% respectively.Conclusion Among the body size indices, genes play important roles in the development of Height, Weight, WHR and BMI in adolescent, WHR is also influenced by environmental factors to some extent, waist circumference is nearly influenced by environmental factors, so obesity in adolescents can be prevented by changing their environmental factors.