Human genomic library was screened by plauqe hybridizaion method using human total tRNAs as a probe. At first screening, 42 recombinant Charon 4A phages were obtained. When 20 of them were further screended, 13 positive phage clones were isolated. Characterization of the phage DNAs revealed that four genes hybridized with human tRNA were contained in different restriction fragments. From the clones, two genes were subcloned and partial nucleotide sequence of one was determined. The nucleotide sequence did not contain tRNA coding gene. And two genes were not trascribed by RNA polymerase III in an in vitro transcription reaction using HeLa nuclear extract. It seems that human total tRNA used as a probe was not pure and unknown RNA coding genes were screened by this experiment.
