| 摘要 |
PURPOSE:To provide the subject new DNA fragment coding a polypeptide useful for diagnosis of non-A, non-B hepatitis excellent in accuracy of judgment. CONSTITUTION:This invention is a DNA fragment obtained by collecting non-A, non-B hepatitis virus RNA directly from the plasma of a non-A, non-B hepatitis patient and modifying the collected RNA according to the genetic engineering method, containing a base sequence capable of coding a polypeptide constituting non-A, non-B hepatitis virus structural protein and having an amino acid sequence of, e.g. the formula. From the fresh plasma of a Japanese chronic non-A, non-B hepatitis patient infected only with group II, all the RNAs including non-A, non-B hepatitis virus RNA are collected using ELISA method and PCR method and cDNA is synthesized according to random primer method. The resultant cDNA is introduced in lambda phage so as to construct a cDNA library. The obtained cDNA library is subjected to immunoscreening using the above- mentioned plasma of the hepatitis patient and cDNA library constructed from plural patient plasmas is screened by using the resultant DNA fragment as a probe, thus affording the objective cDNA specific to the above-mentioned hepatitis. |
