title: Haplotype architecture of the norepinephrine transporter gene SLC6A2 in four populations.
abstract: The norepinephrine transporter (NET) regulates levels of monoamine neurotransmitters integral to a variety of behaviors and autonomic functions. Two SLC6A2 polymorphisms have been used in genetic association studies, generating intriguing but nondefinitive results on traits such as hypertension and mood. One of these SLC6A2 variants is functional but rare. The other is common but not informative over the entire 48 kb SLC6A2 region and is insufficient to capture the functional diversity potentially contained within any SLC6A2 region. To elucidate SLC6A2 haplotype structure and define markers sufficient to capture haplotype diversity within detected haplotype blocks, 26 single-nucleotide polymorphisms (SNPs) were genotyped in 384 individuals evenly divided across Finnish Caucasian, US Caucasian, Plains American Indian, and African American populations. Three conserved blocks, 13.6, 12.5, and 25 kb in size and showing little evidence for historical recombination were observed in all populations. Haplotype diversity in block 1 and numbers of common haplotypes were highest in African Americans, among whom 5-6 optimal markers were sufficient to maximize diversity of each block. For other populations, 2-3 markers/block sufficed, but the optimal markers differed across populations. The SLC6A2 haplotype map and 25-marker panel (excluding the monomorphic one) is a comprehensive tool for genetic linkage studies on phenotypes related to NET function.
authors.affiliation: Pain and Neurosensory Mechanisms Branch, National Institute of Dental and Craniofacial Research, Bethesda, MD, USA. ibelfer@mail.nih.gov
authors.forename: Inna
authors.initials: I
authors.lastname: Belfer
authors.forename: Gabriel
authors.initials: G
authors.lastname: Phillips
authors.forename: Julie
authors.initials: J
authors.lastname: Taubman
authors.forename: Heather
authors.initials: H
authors.lastname: Hipp
authors.forename: Robert H
authors.initials: RH
authors.lastname: Lipsky
authors.forename: Mary-Anne
authors.initials: MA
authors.lastname: Enoch
authors.forename: Mitchell B
authors.initials: MB
authors.lastname: Max
authors.forename: David
authors.initials: D
authors.lastname: Goldman
mesh_terms: D001741:Black or African American / Q000235:genetics; D005387:Finland; D005787:Gene Frequency; D005819:Genetic Markers; D005838:Genotype; D006239:Haplotypes / Q000235:genetics*; D006801:Humans; D007198:Indians, North American / Q000235:genetics; D015810:Linkage Disequilibrium; D050484:Norepinephrine Plasma Membrane Transport Proteins; D011110:Polymorphism, Genetic; D020641:Polymorphism, Single Nucleotide; D027981:Symporters / Q000235:genetics*; D014481:United States; D044465:White People / Q000235:genetics
chemical_list: D005819:Genetic Markers; D050484:Norepinephrine Plasma Membrane Transport Proteins; C493227:SLC6A2 protein, human; D027981:Symporters