Coat genetic markers of the domestic cat Felis catus (Felidae) from southwestern Colombia / Marcadores genéticos del pelaje del gato doméstico Felis catus (Felidae) del suroccidente colombiano

ABSTRACT Objectives. Establish the genetic profiles of cats from 12 neighboring municipalities in southwestern Colombia, in a town course from Pereira-Popayán. Estimate the degree of diversity, genetic structure, and quantify gene flow. Materials and methods. Were inventoried the phenotypic markers present in the pigmentation and structure of the coat of 1482 cats of the municipalities surveyed. Based on these phenotypic frequencies, allele frequencies, heterozygosity, Hardy-Weinberg equilibrium, F statistics and Nei genetic distances were calculated. A comparison was also made between genetic and geographic distance matrices to determine if there was a significant association between the two. Results. With the genetic profiles of the populations we estimated the degree of diversity. We found the populations in equilibrium for the S autosomal locus and for the O sex-linked locus. We found a low level genetic structure, and it was determined that there was no significant correlation between the genetic and geographic distance matrices among populations. Conclusions: These findings can be explained on the basis of the processes of human displacement for this region, due to the fact that the establishment of feline populations in these municipalities originated during the same historical period. Identical genetic profiles are shared as a result of colonization events, and due to possible continued migration among these populations.

RESUMEN Objetivos. Determinar los perfiles genéticos de los gatos de 12 municipios contiguos del suroccidente colombiano en un trayecto Pereira-Popayán; estimar el grado de diversidad, estructura genética y cuantificar el flujo de genes. Materiales y métodos. Se inventariaron los marcadores fenotípicos presentes en la pigmentación y estructura del pelaje de 1482 gatos de los municipios estudiados, con base en estas frecuencias fenotípicas se calcularon frecuencias alélicas, heterocigosidad, equilibrio Hardy-Weinberg, el estadístico FST y distancias genéticas de Nei. También se realizó una comparación entre matrices de distancia genética y geográfica para determinar si existía asociación significativa entre las dos. Resultados. Con los perfiles genéticos de las poblaciones se estimó el grado de diversidad, se halló en equilibrio Hardy-Weinberg a las poblaciones para el locus autosómico S y el locus ligado al sexo O. Se encontró bajo nivel de estructura genética y se determinó que no existe correlación significativa entre las matrices de distancia genética y geográfica entre poblaciones. Conclusiones. Estos hallazgos se pueden explicar con base en los procesos de desplazamiento humano para esta región, debido a que el establecimiento de poblaciones felinas en estos municipios se originó en el mismo período histórico. Se comparten perfiles genéticos idénticos como resultado, posiblemente, de eventos de colonización y migración continua entre estas poblaciones.

Sequence variation in the melanocortin-1 receptor (MC1R) pigmentation gene and its role in the cryptic coloration of two South American sand lizards

In reptiles, dorsal body darkness often varies with substrate color or temperature environment, and is generally presumed to be an adaptation for crypsis or thermoregulation. However, the genetic basis of pigmentation is poorly known in this group. In this study we analyzed the coding region of the melanocortin-1-receptor (MC1R) gene, and therefore its role underlying the dorsal color variation in two sympatric species of sand lizards (Liolaemus) that inhabit the southeastern coast of South America: L. occipitalis and L. arambarensis. The first is light-colored and occupies aeolic pale sand dunes, while the second is brownish and lives in a darker sandy habitat. We sequenced 630 base pairs of MC1R in both species. In total, 12 nucleotide polymorphisms were observed, and four amino acid replacement sites, but none of them could be associated with a color pattern. Comparative analysis indicated that these taxa are monomorphic for amino acid sites that were previously identified as functionally important in other reptiles. Thus, our results indicate that MC1R is not involved in the pigmentation pattern observed in Liolaemus lizards. Therefore, structural differences in other genes, such as ASIP, or variation in regulatory regions of MC1R may be responsible for this variation. Alternatively, the phenotypic differences observed might be a consequence of non-genetic factors, such as thermoregulatory mechanisms.