Hox基因在所有动物沿身体轴线的结构分化中都扮演一个中心角色，该基因表达模式的改变与脊椎动物身体构造的多样化并行。

对有鳞爬行类（蜥蜴和蛇）Hox基因的组织所做的一项研究表明，Hox基因簇出人意料地积累了可转座的元素，反映了编码和非编码调控区域中广泛的基因组重排。对表现出不同中轴骨架的两个物种（玉米蛇和鞭尾蜥）所做的比较表达分析显示，Hox13 和 Hox10的表达有很大改变，与发育中的蛇胚胎的尾部区域和胸部区域的扩张巧合。

因此，Hox基因簇结构和功能的改变可能反映了在这一类群中所观察到的广泛的形态辐射。

原始出处：

Nature 464, 99-103 (4 March 2010) | doi:10.1038/nature08789

Changes in Hox genes' structure and function during the evolution of the squamate body plan

Nicolas Di-Po?1, Juan I. Montoya-Burgos1, Hilary Miller2, Olivier Pourquié3,4,6, Michel C. Milinkovitch1 & Denis Duboule1,5

1 National Research Center ‘Frontiers in Genetics’, Department of Zoology and Animal Biology, University of Geneva, Sciences III, 1211 Geneva 4, Switzerland
2 School of Biological Sciences, Victoria University of Wellington, Wellington 6140, New Zealand
3 Howard Hughes Medical Institute,
4 Stowers Institute for Medical Research, Kansas City, Missouri 64110, USA
5 School of Life Sciences, Federal Institute of Technology (EPFL), 1015 Lausanne, Switzerland
6 Present address: Institute de Génétique et de Biologie Moléculaire et Cellulaire, CNRS (UMR 7104), Inserm U964, Université de Strasbourg, Illkirch, F-67400, France.

Hox genes are central to the specification of structures along the anterior–posterior body axis1, 2, and modifications in their expression have paralleled the emergence of diversity in vertebrate body plans3, 4. Here we describe the genomic organization of Hox clusters in different reptiles and show that squamates have accumulated unusually large numbers of transposable elements at these loci5, reflecting extensive genomic rearrangements of coding and non-coding regulatory regions. Comparative expression analyses between two species showing different axial skeletons, the corn snake and the whiptail lizard, revealed major alterations in Hox13 and Hox10 expression features during snake somitogenesis, in line with the expansion of both caudal and thoracic regions. Variations in both protein sequences and regulatory modalities of posterior Hox genes suggest how this genetic system has dealt with its intrinsic collinear constraint to accompany the substantial morphological radiation observed in this group.