Kay E D
Department of Oral Anatomy, College of Dentistry, University of Illinois, Chicago 60612.
J Embryol Exp Morphol. 1986 Nov;98:123-36.
Evidence from studies of craniofacial anomalies and the evolutionary transition from reptiles to mammals suggests that the temporomandibular joint (TMJ), bony zygomatic arch, middle ear ossicles and mandibular muscle pattern may form a correlated suite of characters. To test the degree of phenotypic interdependence among these features, mandibular arch defects were analysed in prenatal mice. Retinoic palmitate was administered to pregnant mice on day 8.7 to produce test foetuses with malformations of the mandibular arch. A rating scale was developed for each of the four characters so that numerical values could be assigned to each phenotype encountered. Control animals were used to establish normal phenotypes for each character which were assigned a value of 1. Data from each test age, 16, 18 and 19 days postconception, were pooled and Spearmann rank correlation coefficients between each of the traits were calculated. Coefficients (R) range from a high of 0.87, between the TMJ and zygomatic arch, to a low of 0.67 between the zygomatic arch and the mandibular musculature showing highly significant correlations (P less than 0.0001) among all characters. Therefore, the data suggest that the musculoskeletal features of the mandibular arch are phenotypically interdependent during development.
来自颅面异常研究以及从爬行动物到哺乳动物的进化转变的证据表明，颞下颌关节（TMJ）、骨性颧弓、中耳听小骨和下颌肌肉模式可能构成一组相关的特征。为了测试这些特征之间表型相互依赖的程度，对产前小鼠的下颌弓缺陷进行了分析。在妊娠第8.7天给怀孕小鼠施用视黄酸棕榈酸酯，以产生具有下颌弓畸形的试验胎儿。为这四个特征中的每一个制定了一个评分量表，以便可以为遇到的每种表型赋予数值。使用对照动物来确定每个特征的正常表型，并将其赋值为1。汇总来自每个测试年龄（受孕后16、18和19天）的数据，并计算每个性状之间的Spearmann等级相关系数。系数（R）范围从TMJ与颧弓之间的0.87到颧弓与下颌肌肉组织之间的0.67，表明所有特征之间具有高度显著的相关性（P小于0.0001）。因此，数据表明下颌弓的肌肉骨骼特征在发育过程中表型上是相互依赖的。
