Human cDNA Clones Containing Homeo Box Sequences

One of the central aims of developmental biology is to understand the molecular mechanisms governing the precise control of differentiation processes. Early in the development of many metazoans, cells in different regions of the embryo are committed to separate fates based on their position. These separate fates result eventually in a differential pattern of morphogenesis in different regions of the embryo. A conserved basic pattern in animal embryogenesis is that of metamerism, in which groups of cells are organized into morphologically distinct segments. It is of great interest to identify the genetic loci in vertebrates that determine pattern formation and developmental pathways. Unfortunately, the genetics of most vertebrates does not easily lend itself to this type of analysis. In contrast, a number of loci in Drosophila have been defined that are implicated in directing the formation of distinct body segments (Ouweneel 1976). These include the homeotic genes (Lewis 1978), which...