Abstract: In transcriptomics analysis, we sometimes find that transcripts are composed of non-co-linear sequence fragments (the so-called “chimaeric transcripts”), which are pieces of mRNA sequences that come from distant regions of DNA (even different chromosomes). In the past the anomaly transcripts (i.e., non-co-linear sequence fragments) are usually regarded as abnormal products and removed out during the gene-finding processes. Recently, a considerable number of chimaeric transcripts were observed and proved to be true in normal human cells. By EST-to-genome comparisons, previous studies have identified thousands of chimaeric transcripts in fly, mouse, and human. However, recent reports indicated that most predicted chimaeric RNAs might be false positives derived from a result of problematic alignments or simply an artifact of the sequencing protocol; only a handful of cases have been validated to recurrently occur in cells. The chimaeric transcripts may result from genetic rearrangements or post-transcriptional events (i.e., trans-splicing events). The mechanism of trans-splicing events is still unclear. In human, two of the most striking trans-splicing events are JAZF1-JJAZ1 and SLC45A3-ELK4. The former case may be a precondition for chromosomal exchange; meanwhile the later may be associated with the treatment of the LNCaP cell line with R1881 synthetic androgen. The identification and analysis of human trans-splicing events can increase our understanding of primate transcriptomics evolution and complexity of genetic system.