Singleton gene expressed in adipose tissue
The vast majority of genes are expressed in multiple tissues and organs, reflecting their multi-functional nature. However, there exist a subset of genes called “singletons” that are present only in one specific cell type. Insulin is a classic example of a singleton gene, expressed solely in pancreatic β-cells. These singletons are very attractive therapeutic targets because of their finite function.
Drugs targeting such genes may have a lower risk of unwanted effects compared to drugs acting on multifunctional targets. Out of the 200+ genes studied by Cytochem, several were shown to be singletons, including erythropoiesis-specific, adipocyte-specific, osteoblast-specific, endothelium-specific, Schwann-cell-precursor-specific and neuron-specific genes (see photo gallery)