Structure and localization of the human SULT1B1 gene: Neighborhood to SULT1E1 and a SULT1D pseudogene

The soluble sulfotransferases are involved in the elimination of xenobiotic s, the activation of procarcinogens, and the regulation of hormones. They c omprise a gene superfamily (SULT). The structure and chromosomal location o f nine human SULT genes are known. We have characterized a further gene, SU LT1B1. Its structure is similar to that of other SULT1 genes. However, the total length of its eight exons and the introns (33.6 kb) is larger than th at of other human SULT1 genes (4 to 21 kb). The SULT1B1 gene sequence is pa rt of a sequence entry in the unfinished High-Throughput Genomic Sequences (HTGS) division of Genbank. However, the order and orientation of the SULT1 131 exons are not correct in this entry. SULT1B1 is located on chromosome 4 q13.1, nearly 100 kb downstream of SULT1E1 on the same strand. The interven ing sequence contains a SULT-like structure showing substantial homology to the mouse SULT1D1 cDNA recently described. However, in humans this structu re represents a pseudogene (SULT1D1P) because of mutated splice donors/acce ptors and in-frame stop codons in the sequence corresponding to exon II. Th is SULT gene cluster is located on the minus strand of chromosome 4 with SU LT1B1 being closest to the centromer. (C) 2001 Academic Press.