HOX gene

Homeotic genes, often referred to as HOX genes in vertebrates, are crucial for orchestrating body formation during early embryonic development. These genes produce transcription factor proteins that control the expression of other genes, guiding cells to develop into specific body parts. A key feature of these genes is the presence of a DNA sequence called a homeobox, which encodes a specific segment within the transcription factor protein. Mutations in homeobox genes can lead to significant developmental abnormalities, such as the famous antennapedia mutation in fruit flies where legs grow on the head instead of antennae. HOX genes are highly conserved across a wide range of organisms, from fungi to plants and vertebrates, highlighting their fundamental role in establishing body plans. Humans have approximately 39 HOX genes organized into four clusters on different chromosomes.12