Seven Novel Single Nucleotide Polymorphisms in the Human SLC22A1 Gene Encoding Organic Cation Transporter 1 (OCT1)

Summary: Twenty genetic variations, including seven novel ones, were found in the human SLC22A1 gene, which encodes organic cation transporter 1, from 116 Japanese individuals. The novel variations were as follows: –94C > Ain the 5′-untranslated region (A of the translation start codon is numbered + 1 in the cDNA sequence; MPJ6_OC1001), 350C > T (MPJ6_OC1004), IVS1–35 T > C (MPJ6_OC1006), 561G > A (MPJ6_OC1010), IVS6 + 75C > G (MPJ6_OC1014), IVS8 + 108A > G (MPJ6_OC1017), and 1671_1673delATG (MPJ6_OC1020). The frequencies were 0.082 for IVS1–35 T > C, 0.022 for IVS6 + 75C > G, 0.009for 561G > A, and 0.004 for the other 4 variations. Among them, 350C > T resulted in the amino acid substitution Pro117Leu, which is located in the large extracellular loop between transmembrane domains 1 and 2. Also, we detected the four previously reported nonsynonymous variations, 123C > G (Phe41Leu), 480C > G (Phe160Leu), 1022C > T (Pro341Leu), and 1222A > G (Met408Val) with frequencies of 0.004, 0.086, 0.168, and 0.810, respectively.