To completely characterize the spectrum of mutations in the cystic fibrosis transmembrane conductance regulator gene in Greek cystic fibrosis (CF) patients, we screened 500 CF chromosomes by denaturing gradient gel electrophoresis followed by direct sequencing. We identified 48 mutations, accounting for 85.6% of CF chromosomes. They included eight novel mutations, three of which we have described before and five (E822X, Y247X, 2752-26A-->G, 3152delT, and 2751 + T-->A), which are described in this report. The detection of such a high proportion of Greek CF mutations is important for improving prenatal and genetic diagnosis of CF in Greece.