Erythrocyte pig-a gene mutation assay (rodent)

Mammalian (rodent) erythrocyte pig-a gene mutation assay is used for calculating the frequency of mutant phenotype erythrocytes/reticulocytes by measuring mutations at the phosphatidylinositol glycan class A (pig-a) gene. 

Glycosylphosphatidylinositol (GPI) anchors bind proteins to the outer surface of mammalian cells. Pig-a is present on the X-chromosome as only one functional copy per cell (unlike the other genes involved which have two). Therefore, cells without GPI anchors/proteins are markers of pig-a gene mutation. Flow cytometry is used to analyze the levels of GPI-anchored protein markers in erythrocytes from small blood samples.