Possibility of Multiple Targets

As is the case with many other nuclear receptors, there are multiple forms of the ER in a cell. There are two major subtypes, named ERa and ER0, which are encoded by 

Nuclear Receptors as Drug Targets. Edited by Eckhard Ottow and Hilmar Weinmann Copyright 2008 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim ISBN 978-3-527-31872-8 

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