Intra-chromosomal recombination of agouti gene in white alpaca

The role of the agouti gene in white phenotype was explored in mice. The agouti signalling protein (ASP) can inhibit the differentiation of melanoblasts through the inhibition of the alfa-MSH-induced expression of microphtalmia (MITF) and its binding to a M box regulatory element. The level of microphtalmia in the cells is reduced. To investigate the role of agouti in this phenotype we characterised the transcript structures an relative mRNA expression levels in 13 white alpaca. The reverse transcription analysis of mRNA purified from skin biopsies revealed the presence of three transcripts with different 5’untranslated regions (UTRs) and color specific expression. One of the transcripts, possibly originating from a duplication event (intra-chromosomal recombination) of the agouti gene is characterised by a 5’UTR containing 142 bp of the NCPOA6 gene sequence. Furthermore, the raltive level expression analysis of mRNA demonstrates that the agouti gene has upregulated expression in white skin, suggesting a pleiotropic effect of agouti gene in the white phenotype.