Data from: Host association drives significant genetic divergence in the bed bug, Cimex lectularius

Genetic differentiation may exist among sympatric populations of a species due to long-term associations with alternate hosts, termed “host-associated differentiation”. While it is often documented in phytophagus insects there is a paucity of empirical studies on this process in parasites. The bed bug, Cimex lectularius, represents a potential model organism for elucidating the processes involved in host-associated differentiation in parasites. In conjunction with the expansion of modern humans from Africa into Eurasia, it has been speculated that bed bugs extended their host range from bats to humans in their shared cave domiciles throughout Eurasia. C. lectularius that associate with humans have a cosmopolitan distribution, whereas those associated with bats co-occur sympatrically with human-associated bugs across Europe. We assessed genetic structure and gene flow within and among populations collected on each host using three classes of markers: mtDNA, microsatellite loci, and knock-down-resistance gene variants. Both nuclear and mitochondrial data support a lack of significant contemporary gene flow between host-specific populations. Within locations human-associated bed bug populations’ exhibit limited diversity and elevated levels of inbreeding, likely due to human-mediated movement, limited additional introduction events per infestation, and pest control. In contrast, populations within bat roosts, located in human associated properties, exhibit higher diversity and lower levels of relatedness, suggesting populations are stable with temporal fluctuations due to host dispersal and bug mortality. In concert with previously published morphological and behavioral results, the genetic data presented here suggests C. lectularius is currently undergoing lineage divergence through host-association.