Glutathione S‐transferase polymorphisms in patients with photosensitive and non‐photosensitive drug eruptions

BACKGROUND: Glutathione S-transferases (GSTs) play a critical role in cellular protection against oxidative damage. Polymorphisms in three major GST loci have been described. A number of studies have looked for an association between GSTs and skin diseases. PURPOSE: To ascertain the possibility that polymorphisms in the GSTM1, GSTT1, and GSTP1 genes may predict the development of photo-induced and non-photo-induced drug eruptions. METHODS: A cohort of 40 patients with drug eruptions, 10 of whom had developed a photo-induced drug reaction, and matched controls (116 for GSTM1 and GSTT1, 120 for GSTP1) were studied. Genotyping was conducted using direct sequencing and polymerase chain reaction. RESULTS: The GSTP1 Val/Val genotype was significantly associated with non-photosensitive drug eruptions (OR = 3.64, P value = 0.038), whereas associations observed between GSTP1, GSTM1, GSTT1 polymorphisms and photosensitive drug eruptions did not reach statistical significance. CONCLUSIONS: Variations in GSTP1 may affect the risk to develop non-photo-induced drug eruptions. These results warrant confirmatory studies in a larger patient sample.