GSTT1 belongs to a superfamily of proteins which catalyze the conjugation of reduced glutathione to a variety of electrophilic and hydrophobic compounds. GSTs can be divided into five main classes: alpha, mu, pi, theta, and zeta(which includes GSTT1 and GSTT2). The GSTT1 gene is haplotype-specific and is absent from 38% of the population. GSTT1-null genotypes are seen as having a higher risk of developing leukoplakia.
