This volume contains the accepted full papers and extended abstracts of the 5th Brazilian Symposium on Bioinformatics held in Bu zios, Rio de Janeiro, Brazil from August 31 to September 3, 2010. The ?rstthree meetings ofthis series, which took place2002,2003, and 2004, were called WOB (Workshop on Bioinformatics). In 2005, the conference got its current name BSB and has since published its proceedings as a special issue of the series Lecture Notes in Bioinformatics (volumes 3594/2005, 4643/2007, 5167/2008, and 5676/2009). Its topics of interest vary in many areas of bioinformatics, including...