This gene was located on chromosome 7 between markers BM596 and BM1444. Its identification demonstrates that one aspect of virulence, i.e. the insect’s preference for resistant rice varieties expressing Bph1, is largely determined by a major gene. To identify virulence factors that countered the antibiosis effect of Bph1, we studied the growth rate of insects feeding on resistant plants rather than honeydew production. In our experience, body weight changes provide more accurate and direct information than honeydew-based approaches. The growth rate varied continuously in the F2 population when it was only allowed to feed on Mudgo plants, but the distribution was clearly bimodal, suggesting monogenic or oligogenic inheritance. Two major QTLs, Qgr5 and Qgr14, were mapped to very narrow segments of chromosome 5 and 14, demonstrating that the virulence that overcame the antibiosis effect of Bph1 was controlled by an oligogenic system. These results advance our understanding of the molecular genetic basis for of virulence in of the N. lugens. In general, insect virulence is governed by components that match the mechanisms of host resistance. In the case of the brown planthopper and rice, the virulence factors affecting host preference act against antixenosis, while those affecting growth rate act against antibiosis. The components of insect virulence might derive from independent genetic characters. The practical implication of this for rice improvement is that the integration of multiple resistance mechanisms into new varieties will delay the formation of new herbivorous insect biotypes. Because resistance to brown planthopper feeding in rice varieties is known to be controlled by major genes, it is widely assumed that there is a gene-for-gene relationship between resistance on the part of the rice plant and virulence on the part of the pest. It will be interesting to carry out fine-scale mapping experiments to isolate the genes responsible for host preference and growth rate, and to identify allelic variations related to virulence: this will shed light on the coevolutionary interactions between plant and insect, and allow us to better understand. The very comprehensive N. lugens linkage map presented in this work will thus provide new insights into the evolution of planthopper genomes and will be a valuable tool for validating genome sequence assemblies, detecting QTLs, map-based cloning, assessments of genetic diversity, and comparative genomic studies. Advances in gene expression profiling have permitted characterization of different intrinsic molecular subtypes present in TNBC. One of these, the claudin-low breast cancer subtype, is characterized by mesenchymal features, low expression of cell-cell junction proteins, and intense immune infiltrates. Furthermore, claudin-low tumors have unique biological properties linked to mammary stem cells and EpithelialMesenchymal Transition features.