GSTT1present

GSTT1present is a genetic designation indicating the GSTT1 gene is present (not deleted) in an individual's genome. GSTT1 belongs to the theta class of glutathione S-transferases and participates in the detoxification of electrophilic compounds by conjugating them with glutathione. The presence of GSTT1 allows for the production of theta-class GST enzymes, though actual enzyme activity depends on expression, copy number, and regulation. A common variant is GSTT1 null (absent) due to a gene deletion, in which case no functional GSTT1 enzyme is produced.

The GSTT1 gene is located on chromosome 22q11.23. A deletion variant can result in a GSTT1-null genotype, whereas GSTT1present indicates one or two copies of the gene. Genotyping for GSTT1 present or null is typically performed using polymerase chain reaction (PCR) based methods; the absence is often inferred when amplification fails, with a separate control gene used for validation.

In research, GSTT1present status has been examined in relation to disease risk and drug response. Since GSTT1 enzymes participate in detoxification of various environmental carcinogens and reactive intermediates, the presence of GSTT1 can influence susceptibility to certain cancers and the metabolism of specific drugs. However, associations are variable across cancer types and populations, and GSTT1 presence does not guarantee protection. Gene-environment interactions and compensatory activity from other detoxification enzymes, such as other GST family members, also shape risk profiles.