p53 sequence polymorphisms in late-stage leukemic Mytilus edulis are homologous with M-trossulus p53

Mytilus edulis and M. trossulus are key species in marine intertidal communities that develop a leukemia-like haemic neoplasia at increased incidences at some polluted sites. The tumor-suppressor p53, known to be involved in this disease, was proposed as a biomarker based on sequence polymorphisms in M. trossulus. In this study, p53 mRNA sequence variations in normal and diseased M. edulis were compared with those reported previously for M. trossulus for caged individuals of both species submerged in Burrard Inlet (49A degrees 20'16.57aEuro(3)N 123A degrees 13'51.37aEuro(3)) in 2007 and 2010. Thirty-seven single nucleotide polymorphisms (SNPs) were detected in M. edulis p53 that formed high linkage disequilibrium blocks associated with late-stage leukemia (p < 0.05). These were found at loci that were more homologous with M. trossulus than with healthy M. edulis p53-predicted haplotypes. Increased susceptibility to this cancer might be due to, in part, p53 alleles containing these SNPs.