Stephen D. Dertinger, Ph.D.
NIEHS Grant R44ES018017
An NIEHS Small Business Innovative Research grantee and colleagues developed a simple method for quickly detecting red blood cells with mutant forms of the PIG-A gene in 100-microliter blood samples. Mutations in the PIG-A gene act as a reporter of in vivo mutation and can be simply and rapidly quantified using flow cytometry. The new assay should prove useful for DNA damage research, including studies of environmental factors that modify normal rates of mutation.
The researchers extended an approach they previously developed in rodent models to analyze reticulocytes and erythrocytes in human blood. To test the approach, they processed and analyzed three independent blood samples from 52 healthy, non-smoking adults. They found that the frequency of PIG-A mutant reticulocytes and erythrocytes increased with donor age. Replicate samples showed little variability in the average PIG-A mutant frequency (about 10 percent for reticulocytes and 2 percent for erythrocytes). However, the researchers observed a 30-fold range in reticulocyte PIG-A mutation frequency between different donors. They also found that people generally had higher frequencies of PIG-A mutant blood cells than rodents.
The researchers say that this new technique should prove valuable for various biomonitoring applications, including the study of accidental chemical or radiation exposures, occupational exposures, drugs undergoing clinical trials, cancer therapy treatments, and population-based epidemiology studies of environmental exposures.
Citation: Dertinger SD, Avlasevich SL, Bemis JC, Chen Y, MacGregor JT. 2015. Human erythrocyte PIG-A assay: An easily monitored index of gene mutation requiring low volume blood samples. Environ Mol Mutagen 56(4):366-377.