Abstract: In this paper we compare the sequence of the gene HSP150/PIR2, independently determined by two different groups, with that present in the yeast database as YJL159w, determined within the Yeast Sequencing Project. Although YJL159w is believed to encode Hsp150/Pir2, there are important differences between the amino acid sequence coded by this ORF and that of HSP150/PIR2. To find out if this divergence is due to strain polymorphism or to a possible sequencing error, we have analysed the diverging zone of this ORF in three strains and have found it entirely consistent with the sequence reported as HSP150/PIR2, concluding that the divergence is probably due to a sequencing error in YJL159w. Copyright 2000 John Wiley& Sons, Ltd.