Mutations in Drosophila melanogaster that are zygotically expressed and control the spatial pattern of development of the embryo. The mutations fall into three classes that are defined by the pattern of cuticular defects they produce. The gap genes are active in contiguous domains along the anteroposterior axis of the embryo and regulate segmentation within each domain. The pair rule genes are expressed in stripes along the blastoderm with a periodicity that corresponds to every other segment. The segment polarity genes regulate the spatial pattern within each segment. See Chronology, 1980, Nüsslein-Volhard and Wieschaus; 1989, Driever and Nüsslein-Volhard; fushi tarazu, Hox genes, hunchback, maternal polarity mutants, metamerism, selector genes.
Subjects: Genetics and Genomics.