sci-biology@gentoo.org Gentoo Biology Project UCHIME is a new algorithm for detecting chimeric sequences. It was developed in collaboration with Brian Haas, Jose Carlos Clemente, Chris Quince and Rob Knight. Chimeras are commonly created during DNA sample amplification by PCR, especially in community sequencing experiments using single regions such as the 16S rRNA gene in bacteria or the fungal ITS region. UCHIME can detect chimeras using a reference database or de novo using abundance information on the assumption that chimeras are less abundant than their parents because they must have undergone fewer rounds of amplification.