The genetic diversity of Oncomelania hupensis robertsoni, intermediate hosts Schistosome japonicum in hilly regions of China using microsatellite markers

Abstract

Abstract Background The elimination of schistosomiasis remains a challenging task, with current measures primarily focused on the monitoring and control of Oncomelania hupensis (O. hupensis) snail, the sole intermediate host Schistosome japonicum. Given the emerging, re-emerging, and persistent habitats of snails, a study on the genetic diversity of snails might be an essential. Objective The aims of this study were to (1) analyze the genetic diversity of O. hupensis robertsoni Yunnan strain (O. h. r. Yunnan strain) using microsatellite DNA markers; and (2) validate the applicability of previously identified microsatellite loci for O. hupensis in hilly regions. Methods A total of 17 populations of O. hupensis from Yunnan Province in China were selected for analysis of genetic diversity by 6 microsatellite DNA polymorphic loci (i.e., P82, P84, T4-22, T5-11, T5-13, T6-27). Results the number of alleles among populations ranged from 0 to 19, with an average of 5. The average ranges of expected (He) and observed (Ho) heterozygosity within populations were 0.506 to 0.761 and 0.443 to 0.792, respectively. The average fixation index within population ranged from − 0.801 to 0.211. The average polymorphic information content (PIC) within population ranged from 0.411 to 0.757, appearing polymorphic for all loci (all PIC > 0.5), except for P28 and P48. A total of 68 loci showed significant deviations from Hardy-Weinberg equilibrium (P < 0.05), and pairwise Fst values ranged from 0.051 to 0.379. The analysis of molecular variance indicated that 88% of the variation exists within snail populations, while 12% exists among snail populations. Phylogenetic trees and principal coordinate analysis revealed two distinct clusters within the snail population, corresponding to "Yunnan North" and "Yunnan South". Conclusion O. h. r. Yunnan strain exhibits a relatively high level of genetic differentiation, with variation chiefly existing within snail populations. All snail could be separated into two clusters. The microsatellite loci P82 and P84 may not be suitable for the classification study of O. hupensis in hilly regions. These findings provide the important information for monitoring and control of snail, and further genetic diversity studies on snail populations.