In order to generate serial analysis of gene expression (SAGE) libraries from very small samples such as microdissected cells, the starting material must first be amplified via PCR or linear amplification of RNA. In microarray experiments, it has been shown that linear amplification of RNA can be used to generate reliable gene expression profiles and leads to the detection of expression differences that are not seen with nonamplified starting material. As the product of the amplification is amplified antisense RNA (aRNA), linear amplification of RNA cannot be used in combination with the conventional SAGE protocol. The aRNA-LongSAGE protocol described herein is an adaptation of the MicroSAGE protocol to the use of aRNA as starting material.