Fine mapping of the human 5-HTR2a gene to chromosome 13q14 and identification of two highly polymorphic linked markers suitable for association studies in psychiatric disorders

The serotonergic system is known to play an important role in a number of psychiatric disorders. Indeed, treatments involving agents that have their pharmacological activities within this system are the mainstay of treatment for disorders such as schizophrenia. It is now widely accepted that many common psychiatric disorders have a familial or genetic component and as a result of this there has been an upsurge in interest in the 5-hydroxytryptamine (5-HT) pathways. A number of groups have attempted to establish whether polymorphism in particular proteins of the serotonergic system may form part of the genetic component of psychiatric disorders, including schizophrenia and anorexia nervosa. However, the data from these studies are conflicting and the problem is compounded by the lack of known polymorphic genetic markers mapping in close proximity to genes encoding proteins envolved directly or indirectly in 5-HT neurotransmission. In the current study, we have fine mapped the gene for 5-HTR2a by radiation hybrid mapping, and we report two new, highly linked, polymorphic markers that are suitable for linkage and association studies.