Growth hormone gene in llama (Lama glama): characterisation and SNPs identification

Abstract

The South American camelids are a source of meat, fibre, leather, transport and other products useful for the economy of populations in the north-west of Argentina. Breeding and exploitation of the llama and alpaca has experienced a notable increase and with it an interest in improving the performance of these taxa. The growth hormone (GH), a peptide hormone synthesised and secreted by the pituitary gland, affects a variety of economically important traits in livestock such as growth performance, milk production and carcass composition. In this study, we characterised the GH gene of llamas from Argentina and identified several single nucleotide polymorphisms (SNPs). As in other mammals, llama GH gene comprises five exons and four introns. Comparison with the coding sequences of the camel, whale, dolphin, pig, cow and sheep showed 99,1%, 96,5%, 96.2%, 94,8%, 90.6% and 90,3% similarity, respectively. Introns were less conserved, particularly intron C which in llama was considerably shorter than in the other compared species. Sequencing of GH gene in a sample of 20 llamas allowed the identification of 8 SNP, mainly located in introns. Nevertheless, one of them was found in the 3’region. We conclude that the polymorphisms such as the ones presented here could be used for developing genetic markers to assay the effect of different genotypes on economically important traits.