Genotypic and allelic frequencies of SULT1A1 polymorphisms in women receiving adjuvant tamoxifen therapy

Breast Cancer Res Treat. 2006 Jan;95(1):13-6. doi: 10.1007/s10549-005-9019-5.


Human sulfotransferase 1A1 (SULT1A1) is involved in the metabolism of a number of substances including 4-hydroxytamoxifen. It has been shown that patients who are homozygous for the variant SULT1A1 *2/*2 have lower catalytic activity. Previous data has suggested that patients with this particular genotype may be at a greater risk of developing breast cancer or not responding to tamoxifen therapy. To date, there is no data within the Hispanic population on the genotypic and allelic frequencies of the SULT1A1 gene. Two hundred and ninety-six patients were genotyped by either restriction fragment length polymorphism (RFLP) or Pyrosequencing for the SULT1A1 exon 7 polymorphism. The genotypic frequency was 0.47 (*1/*1), 0.40 (*1/*2) and 0.13 (*2/*2) in Caucasians and 0.37 (*1/*1), 0.45 (*1/*2) and 0.18 (*2/*2) in Hispanics. Although Hispanics have a higher genotypic frequency of variant genotypes this difference was not statistically significant (p=0.26). SULT1A1 genotype did not correlate with any prognostic or predictive markers associated with breast cancer. Future evaluations will assess the functional significance of this polymorphism on survival.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antineoplastic Agents, Hormonal / therapeutic use*
  • Arylsulfotransferase / genetics*
  • Breast Neoplasms / drug therapy*
  • Breast Neoplasms / enzymology
  • Breast Neoplasms / genetics*
  • Chemotherapy, Adjuvant
  • Female
  • Gene Frequency
  • Genotype
  • Humans
  • Middle Aged
  • Polymerase Chain Reaction
  • Polymorphism, Genetic*
  • Polymorphism, Restriction Fragment Length
  • Prognosis
  • Prospective Studies
  • Tamoxifen / therapeutic use*


  • Antineoplastic Agents, Hormonal
  • Tamoxifen
  • Arylsulfotransferase
  • SULT1A1 protein, human