Three retinoic acid receptors (RAR), structurally homologous to steroid and thyroid hormone nuclear receptors, have recently been cloned. Analysis of the tissue distribution of RARs mRNAs have demonstrated a distinct expression pattern of the receptors' transcripts. Moreover, the RAR beta gene specifically, is autoregulated by RA. These findings suggest that the retinoic acid receptors differentially contribute retinoic acid physiology.