In addition to the P2159L amino acid replacement, which may cause the mutant phenotype, a number of additional amino acid changes are present compared to the U34925 mei-41 GenBank sequence (these "common" mutations are also present in other mei-41 mutant alleles, possibly due to variability present in the mutagenised population). Amino acid replacement: P2159L. Nucleotide substitution: C8924T.