And finally itís time for our Gene of the Month, and this time itís Deadpan. Another of those fruit fly genes, Deadpan was first discovered in 1992 for playing a key role in determining whether a fly will be male or female. The gene encodes a type of molecule known as a transcription factor, which switches genes on, and itís involved in many other roles in the development of an embryonic fly, as well as just its sex. For example, along with other genes called Tramtrack, Phyllopod and Sevenless, Deadpan is involved in building the clusters of light-sensitive cells known as photoreceptors, which make up the repeating units of a flyís compound eye. Although our eyes look very different from a fruit flyís, similar genes are involved in setting up repeating patterns in a human babyís body as it develops in the womb.