%0 Journal Article
%T Modeling horizontal gene transfer (HGT) in the gut of the Chagas disease vector Rhodnius prolixus
%A Scott Matthews
%A Vadrevu Rao
%A Ravi V Durvasula
%J Parasites & Vectors
%D 2011
%I BioMed Central
%R 10.1186/1756-3305-4-77
%X The model predicted an HGT frequency of less than 1.14 กม 10-16 per 100,000 generations at the 99% certainty level. The model was iterated twenty times, with the mean of the ten highest outputs evaluated at the 99% certainty level. Laboratory trials indicated no horizontal gene transfer, supporting the conclusions of the model.The model treats HGT as a composite event, the probability of which is determined by the joint probability of three independent events: gene transfer through the modalities of transformation, transduction, and conjugation. Genes are represented in matrices and Monte Carlo method and Markov chain analysis are used to simulate and evaluate environmental conditions. The model is intended as a risk assessment instrument and predicts HGT frequency of less than 1.14 กม 10-16 per 100,000 generations. With laboratory studies that support the predictions of this model, it may be possible to argue that HGT is a negligible consideration in risk assessment of genetically modified R. rhodnii released for control of Chagas disease.The challenge of controlling vector borne diseases has fueled development of novel strategies that involve genetic manipulation of arthropod vectors. The goal of these strategies is reduction of vector competence, the ability of an arthropod vector to transmit an infectious pathogen. We have described a method, termed paratransgenesis, that involves modification of symbiotic bacteria of an arthropod [1-3]. In this approach a symbiotic bacterium is transformed with foreign genes expressing anti-pathogen agents. We have validated this approach in a control system for Chagas disease involving the triatomine vector Rhodnius prolixus (order Hemiptera, family Reduviidae) and its obligate symbiont, Rhodococcus rhodnii [4]. R. rhodnii resides in the vector gut lumen, in close proximity to Trypanosoma cruzi, the causative agent of Chagas disease. In our system R. rhodnii is genetically modified to export an insect immune peptide, cecropin A,
%U http://www.parasitesandvectors.com/content/4/1/77