One of the genes involved in hair fibre and hair follicle growth is the fibroblast growth factor 5 (FGF5). Mutation of this gene has been associated with long-haired phenotypes in several animal species, including llamas and alpacas. Blood samples were taken from 16 alpacas (9 Huacaya and 7 Suri), 6 llamas (4 Q'aras and 2 Chak'us), one vicuña and one guanaco. The polymorphisms related to fibre growth were analysed from a whole-genome sequence. The c.499≥T mutation was found to be present in both Huacaya and Suri alpaca breeds encoding a shorty protein of 166 amino acids. A one nucleotide deletion, c.351delC and a 12-nucleotide insertion (c.348_349insGCCATATAACAT) were present only in Chak’u breed llamas. This insertion encodes for a short, 119 amino acid protein, that affects the FGF5 gene and that would cause the growth of long fibres. In the case of mutation of c.499C>T, which ...