Exposure Cell type Test groups Effect of exposure Reference
Cigarette smoking Erythrocytes Non-cancer control cohort non-smokers (n=274) and smokers (n=26) No difference in PIG-A mutant cell levels (p=0.186) (Lawrence et al., 2020)
Erythrocytes Male healthy volunteers (n=129) No difference between smoker and non-smoker (p=0.8594). No association between PIG-A and smoking duration (p=0.0541). Association between PIG-A mutant frequency and cigarette pack/years (p<0.0001). (Cao et al., 2016)
Erythrocytes Non-cancer control cohort non-smokers (n=247) and smokers (n=29) Smokers had PIG-A mutant frequencies of over double that of non-smokers (p=0.011) with mutant frequencies of 5.82 (95% CI 2.79–9.52) and 2.8 (95% CI 2.49–3.57) respectively. (Haboubi et al., 2019)
Depleted Uranium
T-Lymphocytes
Gulf war I veterans (n=35) Low-uU (n=22) Vs High-uU (n=13) No significant difference Low-uU mean mutant frequency =18.13\(\pm\)4.85 High-uU mean mutant frequency = 9.45 \(\pm\) 0.81 P = 0.08
(McDiarmid et al., 2011)
Chemotherapy Erythrocytes Patients with different cancer types (n=10) Pre-treatment PIG-A mutant frequency was the same as healthy controls. Minimal changes in mutant frequency during and post therapy except for one patient undergoing Cisplatin and Etoposide therapy who had 3x increase in PIG-A mutant levels. (Dobrovolsky et al., 2011)
Chemotherapy +/- Radiotherapy Erythrocytes Healthy volunteers (n=10) and cancer patients undergoing chemotherapy +/- radiotherapy (n=27) Healthy volunteer PIG-A mutant frequency range = 0.00–5.00 × 10−6 and cancer patients = 0.00–49.67 × 10−6. No pre-treatment blood samples taken so difficult to determine effect of therapy on mutant levels. (Horibata et al., 2016)
Radiotherapy Granulocyte Patients undergoing therapy for breast cancer (n=30). Five patients had previously received chemotherapy. Lower mutant frequency during (p=0.0035) and after radiotherapy treatment (p=0.006) compared to pre-treatment. (Bonetto et al., 2021)
Azathioprine (AZA) Erythrocyte AZA treated inflammatory bowel disease (IBD) patients (n=36) and healthy controls (n=36). IBD patients exhibited a higher MF (6.10 \(\pm\) 4.44 × 10-6) than healthy volunteers (4.97 \(\pm\) 2.74 × 10-6) (P = 0.0489). No association between AZA treatment and MF. (Cao, Wang, Liu, et al., 2020)
Lead Erythrocyte Workers occupationally exposed to lead (n=267) and healthy volunteers from previous study (n=217). PIG-A MFs were significantly higher in lead-exposed workers (10.90 ± 10.7 × 10−6) than in a general population studied previously (5.25 ± 3.6 × 10−6) (p <0.0001). (Cao, Wang, Xi, et al., 2020)
Polycyclic Aromatic Hydrocarbons (PAH) Erythrocyte PAH exposed BBQ restaurant workers (n=70) and healthy controls (n=56). Urinary PAH metabolites measured to determine individual exposure. PAH exposed group had higher PIG-A MFs than healthy controls (p<0.001). A higher PIG-A MF was associated with higher PAH exposure determined by urinary metabolites (p=0.006). (Cao et al., 2021)
Erythrocyte PAH exposed coke oven workers (n=364), newly employed non-exposed controls (n=34) and control group from non-industrially polluted area (n=273). Coke oven workers had higher PIG-A MF’s of 21.01 ± 25.1 x 10-6 compared to 4.3 ± 3.02 x 10-6 for newly employed non-exposed group and 5.45 ± 4.56 x 10-6 for the larger control group from non-industrial city. (Xi et al., 2023)
Benzene Erythrocyte Benzene exposed chemical plant workers (n=104) and controls (n=273) from previous publication (Cao et al., 2016 and Cao et al., 2021). Benzene exposed workers had higher PIG-A MF’s of 15.96 ± 14.41 × 10−6 compared to controls who had an average MF of 5.46 ± 4.56 × 10−6 (p<0.001). Observed a significant association between PIG-A MF and airborne benzene exposure levels (r=0.501, p<0.001) measured by gas chromatography. (Cao et al., 2023)