Xlox
The Xlox genes, also called Pdx genes, are a group of genes found in many, but not all, animals. Xlox genes contain a homeobox DNA sequence and code for proteins that act as transcription factors. The human genome has one Xlox genes, called IPF1, while the orthologous gene in mouse and other vertebrates is called Pdx1. The gene has been lost from the genomes of the fruitfly Drosophila and the nematode Caenorhabditis elegans. In many animals, the Xlox or Pdx gene is part of a ParaHox gene cluster.