An evaluation of differential methylation of ribonucleic acid in cystic fibrosis.

No differences were found in the methylation of total nucleic acids, total 
RNA, DNA, tRNA, or rRNA from lymphocytes or fibroblasts obtained from 
normal subjects, obligate heterozygotes, or individuals with cystic fibrosis. Similar results 
were obtained using four methods for isolation of the nucleic acids. 
The reasons for the failure of two laboratories to discern the 
reported variations in methylation of RNA in the normal, carrier, or 
cystic fibrosis state may be obscure differences in culture conditions or 
conditions of extraction. 