T-box transcription factors are a group of phylogenetically conserved genes that contain a uniquely defining DNA-binding domain, the T-box domain. These genes are believed to be involved in the regulation of development processes, for example the development of limbs, and it is known that haploinsufficiency of multiple T-box proteins results in severe human congenital malformation syndromes, involving craniofacial, cardiovascular, and skeletal structures. TBX 18 has been reported to be involved in numerous development processes and to act as an antiapoptotic factor.