Hox Nomenclature
Hox genes in different phyla have been given different names, which has led to confusion about nomenclature. The complement of Hox genes in Drosophila is made up of two clusters, the Antennapedia complex and the Bithorax complex, which together are referred to as the HOM-C (for Homeotic Complex). Hox genes (for Homeotic transcription factors) in higher vertebrates are generally arranged in four clusters: Hoxa, Hoxb, Hoxc, and Hoxd. Although historically HOM-C genes have referred to Drosophila homologues, while Hox genes referred to vertebrate homologues, this distinction is no longer made, and both HOM-C and Hox genes are called Hox genes.
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