6～12岁女童头影测量中下颌形态遗传作用的纵向分析

Longitudinal genetic effects on mandibular morphology in cephalograms of female twins aged six to twelve years old

目的:利用头影测量对混合牙列期的下颌形态作遗传作用的纵向分析。方法:测量89对双生子女童的头颅侧位片。采用混合纵向观察法,最终得到有效双生子对数183对(其中同卵110对,异卵73对)。利用双生子法对下颌形态作遗传和环境作用的纵向统计分析。结果:3个下颌实际长度、3个下颌高度、3个下颌深度以及下颌角均检测到显著环境因素作用(P<0.05),而下颌实际长度和下颌高度还能够检测到显著遗传因素作用(P<0.05),下颌体的长度GoPo相对容易改变。结论:下颌的实际大小受较强的遗传控制,但也能够检测到环境因素的显著作用。

Objective：To find the longitudinal genetic effects on mandibular morphology in cephalograms of female twins with mixed dentitions.Methods： The sample used in this study consisted of lateral cephalograms of 89 pairs of female twins aged 6-12 years old in Beijing.With a mixed longitudinal method,the effective twins were 183（MZ 110,DZ 73）.With the statistical methods of twins,the genetic and environmental effects were analyzed on mandibular hard tissue morphology.Results： Statistical comparisons revealed significant environmental effects on 3 measurements of true mandibular length,3 of height,3 of depth and the mandibular angle（P〈0.05）,whilst genetic effects on 3 measurements of mandibular length and height were significant（P〈0.05）.The length of GoPo was the most subjective to environment change.Conclusion： The effect of genetics on the true mandibular size is strong,while environmental impact also can be founded.