Condiciones óptimas de cultivo de linfocitos y análisis parcial del cariotipo de la tortuga cabezona, Caretta caretta (Testudines: Cheloniidae) en Santa Marta, Caribe Colombiano

Abstract

Lymphocyte culture and partial karyotype of the marine turtle Caretta caretta (Testudines: Cheloniidae) in Santa Marta, Colombian Caribbean. Over the past few years an important reduction in the number of nesting marine turtle Caretta caretta individuals has been registered in the Colombian Caribbean, raising the question of a possible extinction in the medium term. A conservation plan is needed. We studied the culture requirements for C. caretta lymphocytes and preliminary karyotype analysis for cytogenetic identification, immunological study and toxicology without the need to kill individuals. Peripheral blood samples were obtained from 47 individuals in Santa Marta, Colombia and tests were made until optimal conditions were established for lymphocyte culture. The karyotype had 56 chromosomes, 32 macrochromosomes and 24 microchromosomes. An ideogram showed that C. caretta has four groups of chromosomes. Sexual chromosomes were not observed. These results do not coincide with the karyotype described from the Pacific (Japan). The present study is the first to include a complete description of the chromosome morphology of turtles from the Atlantic Ocean. it is possible that one of the adaptive strategies of this species is genetic interchange with other species of the family, producing viable hybrids. individuals in this study might be viable hybrids of C. caretta and further molecular studies are needed.

Comparative Cytogenetics of Four Sea Turtle Species (Cheloniidae): G-Banding Pattern and in situ Localization of Repetitive DNA Units

“…The data on sea turtles obtained here allowed us to detect similar karyotypes and indicate probable maintenance of synteny in major chromosome pairs, as suggested in former studies [Bickham et al, 1980;López et al, 2008;Fukuda et al, 2012Fukuda et al, , 2014. The same G-banding chromosome pattern can be detected in some macrochromosomes of species closely related to Cheloniidae, as described by Montiel et al [2016].…”

“…As such, the 2n = 56 chromosome karyotype possibly gave rise to other karyotypes through chromosomal differentiation events in the Cryptodira suborder [Bickham and Carr, 1983]. In addition, previous classic cytogenetic data show a highly conserved karyotype among sea turtles [Bickham et al, 1980;Bickham and Carr, 1983;López et al, 2008;Fukuda et al, 2012Fukuda et al, , 2014.…”

“…In addition, cytogenetic studies in turtles have demonstrated that numerous chromosomal rearrangements, e.g., chromosome fusion, fissions, and inversions, occurred during karyotype lineage differentiation [Valenzuela et al, 2014;Montiel et al, 2016;Cavalcante et al, 2018;Lee et al, 2019;Mazzoleni et al, 2019]. Despite the chromosomal diversity among extant turtles, previous noncomparative cytogenetic studies on sea turtle species have described identical karyotypes [Bickham and Carr, 1983;López et al, 2008;Fukuda et al, 2012Fukuda et al, , 2014. In the present study, the karyotypes of C. mydas, C. caretta, E. imbricata, and L. olivacea were compared, and the data suggest that minor chromosomal changes occurred during the karyotypic evolution of the group.…”

Heterochromatin and microsatellites detection in karyotypes of four sea turtle species: Interspecific chromosomal differences

“…Sea turtles have been studied from a cytogenetic point of view (Bickham et al, 1980;Bickham and Carr, 1983;López et al, 2008;Fukuda et al, 2014), but the lack of comparative karyotype studies prevents a more robust analysis of evolutionary chromosomal changes. The first comparative cytogenetic study in sea turtles was conducted by Machado et al (2020) based on G-banding and in situ location of 18S rDNA and telomere sequences.…”

Los cromosomas de las tortugas tropicales: Kinosternon leucostomum, Trachemys scripta y Staurotypus triporcatus (Testudines: Kinosternidae/Emydidae)

“…Así como aquellas investigaciones relacionadas con los usos y costumbres en países como México, donde varias especies forman parte de las tradiciones arraigadas a varias culturas entre ellas la Olmeca, Maya y Tolteca (West et al, 1987). Por otro lado, estudios recientes de biología que permitan dar mayor comprensión a la ecología y diversidad genética de las especies, han sido limitados solo a especies de origen marino, dada su importancia compartida entre los países, donde varias especies se distribuyen y reproducen; no siendo dicho fenómeno el caso de las especies de agua dulce y terrestres (Reed et al, 1991;Camacho-Mosquera & Amorocho, 2008;López, Hernández-Fernández, & Bernal-Villegas, 2008). Desde la perspectiva de la genética básica y molecular, se le ha dado mayor importancia a los anfibios (Hillis, 1991;Schmid et al, 2010), siendo limitados los estudios en el grupo de los reptiles dulceacuícolas y terrestres.…”