Identification of a deletion variant in the gene encoding the human alpha(2A)-adrenergic receptor

Objective: The alpha (2)-adrenergic receptors are involved in the effects o f catecholamines on energy metabolism. Of three known subtypes with differe ntial expression, alpha (2A)-adrenergic receptors are also localized in adi pose tissue where they counteract the lipolytic activity of beta -adrenergi c receptors. This study was undertaken to assess whether variants in the al pha (2A)-adrenergic receptor gene are associated with body weight. Design and methods: Single strand conformation polymorphism (SSCP) screenin g and subsequent sequencing were applied to determine genetic variants in D NA samples from individuals with obesity, those of normal weight and those underweight. Results: Analysis of the coding region resulted in the identification of an 18 bp deletion, with no other mutation found. Of 429 genotyped subjects, 7 carried the deletion, with no significant differences between lean and obe se subjects. A previously identified polymorphism in the promoter of the al pha (2A)-adrenergic receptor gene also did not show an association with any of the tested body weight categories. Conclusion: Our data suggest that variants in the alpha (2A)-adrenergic rec eptor gene are unlikely to contribute to the predisposition for the lean or obese state.