Jasmine Gipson, from Kennesaw State University, worked with Dr. Kelly Dyer in the UGA Genetics department to study the transmission of Wolbachia, a parasite of insects.
Abstract: Wolbachia is an endosymbiont parasite that lives in the reproductive system 70% of all insects. It is passed down vertically to its offspring from the mother. Wolbachia occurs naturally in D. recens, but not D. subquinaria. In the wild, D. recens and D. subquinaria hybridize and about 2-3% of those hybrid offsprings contain a D. recenâ’s mitochondria, but not the wolbachia. This is a strange situation because the mitochondria is only passed down through the mother’s eggs, just like wolbachia. So how is it possible to have a D. recenâ’s mitochondria, but not the wolbachia as well? This peculiar scenario led to the question, is the transmission rate of wolbachia lower in hybrids compared to pure species? To answer this question, a D. recens female was crossed with a D. subquinaria. The F1 hybrid female was then backcrossed to a D. subquinaria male. The F1 and F2 generations were both test for wolbachia using PCR. The transmission rate for the F1 generation had a transmission rate of 100% and the F2 generation had a transmission rate of 95.7%. This shows that the transmission rate of wolbachia is lowered in hybrid species compared to pure species. Possible explanations for this decrease in transmission rate is because of the genetic variation between D. recens and D. subquinaria or the parasite could have been randomly loss due to oogenesis.