RESUMO
Guinea pigs are a major source of animal protein for Peruvian Andean families. Despite the economic and cultural relevance of guinea pigs, their genomic characterization has been scarcely addressed. Genotyping-by-sequencing (GBS) has emerged as an affordable alternative to genotyping of livestock and native animals. Here, we report the use of GBS for single nucleotide polymorphism (SNP) discovery of traditionally raised guinea pigs from six regions of the Peruvian Andes and one group of breeding animals. The paired-end (2 × 150 bp) sequencing of 40 guinea pig DNA samples generated a mean of 6.4 million high-quality sequencing reads per sample. We obtained an average sequencing depth of 10× with an 88.5% mapping rate to the Cavia porcellus reference genome. A total of 279 965 SNPs (102 SNPs/Mbp) were identified after variant calling and quality filtering. Based on this SNP set, we assessed the genetic diversity and distance within our selected guinea pig populations. An overall average minor allele frequency of 0.13, an observed heterozygosity of 0.31, an expected heterozygosity of 0.35, and an F-value of 0.1 were obtained, while the SNP-based neighbor-joining tree suggests a closer genetic relationship between individuals from geographically close locations. We showed that GBS is a cost-effective tool for SNP discovery and genetic characterization of Peruvian guinea pig populations. Therefore, it may be considered as a suitable and affordable tool for genomic characterization of poorly studied native animal species.
Assuntos
Genoma , Polimorfismo de Nucleotídeo Único , Humanos , Animais , Cobaias , Genótipo , Peru , Genômica , Sequenciamento de Nucleotídeos em Larga EscalaRESUMO
El objetivo fue identificar y predecir la ubicación de polimorfismos de nucleótido simple (PNSs) en genes relacionados al crecimiento de la fibra. Se realizó el estudio con un total de 31 genes de queratina (KRT9, KRT12, KRT13, KRT14, KRT16, KRT18, KRT20, KRT25, KRT1, KRT3, KRT5, KRT6a, KRT6b, KRT6c, KRT7, KRT8, KRT71, KRT80, KRT31, KRT32, KIRT40, KRT81, KRT82, KRT10, KRT15, KRT17, KRT19, KRT2, KRT4, KRT79 y KRT83) asociados con las características de lana, fibra y pelo en ovinos, cabras y humanos respectivamente, cuyas secuencias fueron encontradas en la base de datos del National Center for Biotechnology Information (NCBI). Mediante el uso de bases de datos y herramientas bioinformáticas como el Conserved Domains Database, Spling, y MegaBlast se logró ubicar secuencias únicas para cada gen. Estas secuencias fueron comparadas con los genomas de referencia Vicugna_pacos-2.0.2 y Vi_pacos_V1.0. Se identificaron 48 PNSs ubicados en las regiones intrónicas y exónicas de 22 genes. No se localizaron PNSs en o alrededor de los genes KRT10, KRT15, KRT17, KRT19, KRT2, KRT4, KRT6b, KRT6c y KRT79. El análisis comparativo entre las cuatro especies estudiadas permitió observar que los genes KRT81, KRT6b y KRT6c no están presentes en los genomas de referencia de alpaca, los genes KRT31, KRT14, KRT81, KRT83, KRT6b y KRT6c no están presentes en el genoma de referencia de ovino y los genes KRT31, KRT13, KRT81, KRT83, KRT6b y KRT6c no están presentes en el genoma de referencia de cabra.
The objective was to identify and predict the location of single nucleotide polymorphisms (SNPs) in genes related to fiber growth. The study was carried out with 31 keratin genes (KRT9, KRT12, KRT13, KRT14, KRT16, KRT18, KRT20, KRT25, KRT1, KRT3, KRT5, KRT6a, KRT6b, KRT6c, KRT7, KRT8, KRT71, KRT80, KRT31, KRT32, KIRT40, KRT81, KRT82, KRT10, KRT15, KRT17, KRT19, KRT2, KRT4, KRT79 y KRT83) associated with wool, fiber and hair characteristics in sheep, goat and human, respectively. These gene sequences were retrieved from the National Center for Biotechnology Information (NCBI) database. Using databases and bioinformatics tools such as the Conserved Domains database, Spling and Megablast, unique sequences for each gene were identified. These sequences were compared to the reference genomes: Vicugna_pacos-2.0.2 and Vi_pacos_V1.0 to identify single nucleotide polymorphisms (SNPs). In this manner, 48 SNPs were identified and localized in both intronic and exonic regions of 22 genes. We did not identify SNPs for KRT10, KRT15, KRT17, KRT19, KRT2, KRT4, KRT6b, KRT6c and KRT79. Comparative analysis among the four species studied allow to identify that sequences for KRT81, KRT6b and KRT6c genes are not present in the alpaca reference genomes. Similarly, genes KRT31, KRT14, KRT81, KRT83, KRT6b and KRT6c are not present in the ovine reference genome and, genes KRT31, KRT13, KRT81, KRT83, KRT6b and KRT6c are not present in the goat reference genome.