Research Article

Genetic diversity in populations of the viper Bothrops moojeni Hoge, 1966 in Central Brazil using RAPD markers

Published: July 08, 2008
Genet. Mol. Res. 7 (3) : 603-613 DOI: 10.4238/vol7-3gmr413

Abstract

Bothrops moojeni is an abundant venomous snake responsible for most of the snakebite cases in the Central region of Brazil and as a result of the anthropogenic habitat disturbance, such as the increase in extensive farming, the range of B. moojeni has been greatly fragmented. Here, we obtained genomic DNA from a total of 75 snakes belonging to four populations. Genetic variability evaluated for five RAPD primers was low (He = 0.20) and was not spatially structured. We found evidence of significant genetic divergence among B. moojeni populations that were isolated (ΦST values of 0.21 and 0.25), while populations more proximal exhibited less divergence (ΦST values of 0.04 and 0.08). We found only moderate divergence (ΦST value of 0.12) between two populations greatly isolated (851.83 km apart) along with great differentiation (0.24) between two proximal populations (290 km apart). Even though these populations are close to each other, they occur in an urbanized area that is almost completely covered by extensive crops, representing an obstruction to the mobility of this viper. Molecular variance analysis (AMOVA) showed some degree of subdivision in these populations, with a ΦST value of 0.16, significant to the level of 1% by 1000 random permutations. We also performed a Bayesian analysis that confirmed the AMOVA results and found a value of θB = 0.14 and an ƒ = 0.27, suggesting a high level of endogamy. This is the first study that characterizes genetic variability for this important species of the Bothrops genus, and our data are of significant importance in terms of classifying populations in relation to their conservational value and management strategies. Thus, given the high levels of population structure found in this case, we recommend sampling as many populations as possible to maximize the genetic variability to be preserved when aiming for in situ conservation. The same should be done to perform samplings toward ex situ conservation.

Bothrops moojeni is an abundant venomous snake responsible for most of the snakebite cases in the Central region of Brazil and as a result of the anthropogenic habitat disturbance, such as the increase in extensive farming, the range of B. moojeni has been greatly fragmented. Here, we obtained genomic DNA from a total of 75 snakes belonging to four populations. Genetic variability evaluated for five RAPD primers was low (He = 0.20) and was not spatially structured. We found evidence of significant genetic divergence among B. moojeni populations that were isolated (ΦST values of 0.21 and 0.25), while populations more proximal exhibited less divergence (ΦST values of 0.04 and 0.08). We found only moderate divergence (ΦST value of 0.12) between two populations greatly isolated (851.83 km apart) along with great differentiation (0.24) between two proximal populations (290 km apart). Even though these populations are close to each other, they occur in an urbanized area that is almost completely covered by extensive crops, representing an obstruction to the mobility of this viper. Molecular variance analysis (AMOVA) showed some degree of subdivision in these populations, with a ΦST value of 0.16, significant to the level of 1% by 1000 random permutations. We also performed a Bayesian analysis that confirmed the AMOVA results and found a value of θB = 0.14 and an ƒ = 0.27, suggesting a high level of endogamy. This is the first study that characterizes genetic variability for this important species of the Bothrops genus, and our data are of significant importance in terms of classifying populations in relation to their conservational value and management strategies. Thus, given the high levels of population structure found in this case, we recommend sampling as many populations as possible to maximize the genetic variability to be preserved when aiming for in situ conservation. The same should be done to perform samplings toward ex situ conservation.