As part of our continuing efforts to accumulate information on the coding region of unidentified human genes, we newly determined the sequences of 40 cDNA clones of human cell line KG-1 which correspond to relatively long and nearly full-length transcripts, and predicted the coding sequences of the corresponding genes, named KIAA0161 to 0200. The average size of the cDNA clones analyzed was approximately 5.0 kb. A computer search of the sequences in public databases indicated that the sequences of 20 genes were unrelated to any reported genes, while the remaining 20 genes carried sequences which show some similarities to known genes. Among the genes in the latter category, KIAA0167 contained a Zn-finger motif with significant structural similarity to that of the yeast transcription factor GCS1, and KIAA0189 was classified into the RhoGAP gene family. Stretches of typical CAG (Gln) repeats, which were often correlated with genetic disorders, were found in KIAA0181 and KIAA0192. Another novel repeat composed of alternating Arg and Glu was identified in KIAA0182. Northern hybridization analysis demonstrated that 10 genes are expressed in a cell- or tissue-specific manner.