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<p>Classical genetic studies have identified different coat colour loci in rabbit and comparative analyses have established corresponding loci across species.  In particular, the rabbit <em>dilute</em> locus is determined by a recessive coat colour mutation that modifies the basic colours influenced by the <em>agouti</em> and <em>extension</em> mutations.  In mice, similar phenotypic effects are determined by a similarly named locus.  This locus encodes the myosin VA (<em>Myo5a</em>) gene, whose protein product is an unconventional myosin that plays an essential role in melanosome transport in the melanocytes.  We selected the same gene as a strong candidate for explaining the <em>dilute</em> coat colour in rabbit. To this end, 1399 bp were re-sequenced, spanning 4 exons out of 41 exons and a portion of intronic regions of the rabbit <em>MYO5A</em> gene to identify polymorphisms that could be useful to confirm or exclude this gene as causative of the rabbit <em>dilute</em> locus.  Nine polymorphisms were identified, one of which was used to follow the segregation of the blue and black colours in a Checkered Giant F1 family.  The single nucleotide polymorphism (SNP) analysed did not co-segregate with the two colours.  These results excluded the <em>MYO5A</em> gene as determinant of the <em>dilute</em> locus in rabbit.  The two alleles of this SNP were also present in several other breeds with different coat colours, further indicating that this marker is not associated with the <em>dilute</em> mutation in rabbits.  Other candidates should be investigated to identify the causative gene of this locus in rabbit.</p>