The ADRA2B gene encodes a transmembrane protein belonging to the G protein-coupled family of receptors.  ADRA2B is involved in regulating the release of neurotransmitters, such as norepinephrine and epinephrine, from adrenergic neurons.  By carrying out its function, ADRA2B is believed to play a role in the regulation of smooth muscle contraction and vasoconstriction.

The gene is associated with autosomal-dominant Familial Adult Myoclonic Epilepsy 2 (FAME2), a neurological disorder characterized by involuntary rhythmic myoclonic tremors.  Polymorphisms in the gene have also been associated with an increased risk of Type 2 Diabetes Mellitus (T2DM) and hypertension.  

The ADRA2B gene is located on the long arm of chromosome 2.  It is a 3 kb long intron-less gene.  ADRA2B encodes a protein that is made up of 447 amino acids and has a molecular mass of about 49 kDa.  The gene is highly expressed in the heart.  

A heterozygous insertion/deletion (c.675_686del/ins) in the gene has been associated with FAME2.  In addition, the variant 12Glu9 has been associated with T2DM and hypertension.