Comparison of expression of the fragile site at Xq27 in T and B lymphocytes

We compared the fragile X (fraX) expression in T and B lymphocytes from four hemizygous males with fraX. Blood cultures were stimulated with a T cell mitogen (phytohemagglutinin:PHA) and with a B cell mitogen (pokeweed mitogen:PWM). A significant decrease in fraX expression was observed in cultures stimulated with PWM when compared to PHA-stimulated ones.