GPR182 is a human gene (and associated protein) which is an orphan

Orphan receptor

An orphan receptor is an apparent receptor that has a similar structure to other identified receptors but whose endogenous ligand has not yet been identified. If a ligand for an orphan receptor is later discovered, the receptor is referred to as an "adopted orphan".-Examples:Examples of orphan...

 G-protein coupled receptor.

When this gene was first cloned, it was proposed to encode an adrenomedullin receptor. However when the corresponding protein was expressed, it was found not to respond to adrenomedullin

Adrenomedullin

Adrenomedullin is a peptide associated with pheochromocytoma- a tumour arising from adrenal medulla. It was discovered in 1993.Adrenomedullin is a ubiquitously expressed peptide initially isolated from phaechromyctoma in 1993...

 (ADM).

It was subsequently shown that a different GPCR, CALCRL

CALCRL

Calcitonin receptor-like , also known as the calcitonin receptor-like receptor , is a human protein.- Function :The protein encoded by the CALCRL gene is a G protein-coupled receptor related to the calcitonin receptor...

 when complexed with RAMP2

Receptor activity-modifying protein

Receptor activity-modifying proteins are a class of protein which interact with and modulate the activities of several Class B G Protein-Coupled Receptors including the receptors for secretin, calcitonin , glucagon, and vasoactive intestinal peptide...

can function as an ADM receptor.