The patent pending technology of the ALL-TAIL™ Kit for extreme 3’ RACE, can be used to investigate the dynamic changes in poly(A) tail length that take place during gene expression, as well as the changes in 3’ untranslated regions caused by differential poly(A) tail addition site selection in development, differentiation and cancer. This kit enables the precise measurement of 3’ poly(A) tail length along with the ability to identify and characterize the sequence the 3’ end of RNA transcripts. It can also be used to detect miRNA molecules using a linker ligation technique followed by PCR. Bioo Scientific’s ALL-TAIL Kit provides a sensitive, accurate and highly reproducible assay to measure the poly(A) tail length and the 3’ UTR sequence of any RNA species. First, AIR™ Ligase (a highly efficient truncated T4 RNA ligase 2) efficiently joins an adenylated adaptor oligonucleotide to the 3’ end of the total RNAs. Next reverse transcription is performed using a primer specific to the adenylated adaptor to initiate the production of cDNA. Then a primer designed near the 3’ end of the transcript of interest is used along with the primer specific to the adenylated adaptor to perform PCR amplification of the poly(A) tail and a short stretch of the 3’ UTR. This step may be modified to amplify specific miRNA sequences. Finally, the PCR products are separated on an acrylamide gel and visualized using either SYBR Gold Nucleic Acid Stain or ethidium bromide.