For example, compound receptor mutations which produce abnormalities of pharyngeal and outflow tract similar to 22q11DS include various compound mutants of RARα/β, RARα/γ and RARβ/γ, compound mutants of RXRα with any of the RARs and RXRα mutants alone [71,72,77,78,79,80,81,82]. This evidence concerns the gene RXRA and 22q11.2 deletion syndrome.