Fig. 2

Non-synonymous OCT1 polymorphisms causing potentially functional amino acid substitutions, and their distribution in different world regions. a The localization of the 21 polymorphisms analyzed in details in this study. Substitutions previously reported in the literature to have strong functional effects on OCT1 activity are shown in black (reported loss of function), substitutions predicted to affect OCT1 activity are shown in gray (predicted loss-of-function), and substitutions previously reported to not affect or to cause less than 50 % reduction of OCT1 activity are shown in white (reported to lack strong effects). The polymorphisms are designated with the amino acid substitutions that they cause and the codon that is affected. Their rs-number in the dbSNP database (if available) and their location on chromosome 6 according to the human genome assembly hg19 are also given. b Minor allele frequencies of the 16 known or predicted loss-of-function OCT1 polymorphisms. Shown are 39 populations from Sub-Saharan Africa, North Africa and the Middle East, Central Asia, Europe, and America. The 39 populations shown include 35 populations from the CEPH human genome diversity panel and five from the 1000 Genome Project [24] (designated with 1 K). The populations CEU, ASW, MXL, PUR, and CLM from the 1000 Genomes Project were omitted from these analyses due to their highly admixed structure and/or inability to be allocated to a defined world region