The prevalence of the c-kit exon 10 variant, M541L, in aggressive fibromatosis does not differ from the general population

Background The frequency of the c-kit exon 10 variant, M541L, (c. 1621 A>C) in aggressive fibromatosis (AF) was recently determined to be 2.5-fold higher than in healthy controls. It was thus hypothesised that M541L could be associated with the development of AF. Methods 42 cases of sporadic AF were investigated for c-kit exon 10 alterations, by traditional sequencing. Subsequently, the AF cases and 126 healthy volunteers were screened for the M541L by pyrosequencing. Results Genotype frequency of M541L in AF was 16.7% (allele frequencies: A, 0.92 and C, 0.08), which did not differ from the control group. Moreover the M541L variant was found to be not tumour specific. Conclusions The result classifies the M541L variant of c-kit exon 10 as a single nucleotide polymorphism. Because its prevalence does not differ between the AF and general populations, an association with AF tumourigenesis is unlikely.