In a shotgun approach we sequenced the cosmid pEOA284 containing a fragment derived from the right arm of chromosome XV of Saccharomyces cerevisiae. An analysis of the sequence revealed that it contained open reading frames (ORFs) corresponding to the known genes SLY41, SPS4, COT1, FAA1, PMT3, PRO2 and MYO2. Of the 18 unknown ORFs, five are contained totally within, and two, O6105 and O6163, partially overlap other ORFs. ORF O6116 and O6139 have putative introns. Regions of similarity with chromosomes I and XIII have been uncovered. Interestingly, most of the paired ORFs encode proteins of the same gene family. The relatedness of these ORFs suggests gene duplication.