DETECTION OF DELTA-F508 CYSTIC-FIBROSIS MUTATION BY POLYMERASE CHAIN-REACTION FROM OLD PARAFFIN-EMBEDDED TISSUES - A RETROSPECTIVE AUTOPSY STUDY

This study analyzes the usefulness of the polymerase chain reaction te chnique in the detection of Delta F508 mutation in 11- to 25-yr-old fo rmalin-fixed paraffin-embedded tissues obtained from the autopsy of 38 cystic fibrosis patients (nine with meconium ileus). Two different pa irs of oligonucleotide primers were used: C16 B/C16 D that amplify 98 and/or 95 bp and FQ1/FQ2 that amplify 50 and/or 47 bp. After two indep endent rounds of polymerase chain reactions with the two sets of prime rs, amplification products were obtained in 67.5% of the cases when us ing C16 B/ C16 D primers and in all cases when using FQ1/FQ2 primers. Fifty percent of the chromosomes analyzed in the 29 patients without m econium ileus had the Delta F508 mutation, which was present in 13 het erozygous and 8 homozygous patients. The remaining eight cystic fibros is patients did not carry that mutation. These results are similar to those reported in cystic fibrosis patients from Spain. In the meconium ileus group, we found a higher than expected proportion of Delta F508 mutation; all patients showed the Delta F508 mutation in at least one chromosome, seven patients (77.8%) being homozygous and two (22.2%) h eterozygous. Present results indicate that Delta F508 mutation can be detected by polymerase chain reaction in old paraffin-embedded tissues when appropriate primers are used. Because polymerase chain reaction technique, frequently associated with restriction enzyme analysis, is currently used to detect many other mutations, the use of specially de signed primers to amplify short DNA fragments would permit us to deter mine, in large retrospective autopsy series, whether or not there is a ny correlation between specific genotypes and the severity and specifi city of organ involvement.