noun, plural: segmentation genes
(1) Any of the genes involved in the early stages of pattern formation in the embryo.
(2) A zygotic gene responsible for the formation of body segments.
The segmentation genes are classified into three groups: gap genes, pair-rule genes, and segment polarity genes. In Drosophila, the segmentation genes code for products responsible in forming stripes or segments in the fruit fly embryo.
See also: zygotic gene.