{Reference Type}: Journal Article {Title}: Intrasegmental recombination as an evolutionary force of Lassa fever virus. {Author}: He CQ;Kong C;He M;Chen GX;Liu SM;Ding NZ; {Journal}: Front Microbiol {Volume}: 15 {Issue}: 0 {Year}: 2024 {Factor}: 6.064 {DOI}: 10.3389/fmicb.2024.1411537 {Abstract}: Lassa fever (LF), caused by Lassa virus (LASV), is one of the most dangerous diseases to public health. Homologous recombination (HR) is a basic genetic power driving biological evolution. However, as a negative-stranded RNA virus, it is unknown whether HR occurs between LASVs and its influence on the outbreak of LF. In this study, after analyzing 575 S and 433 L segments of LASV collected in Africa, we found that LASV can achieve HR in both of its segments. Interestingly, although the length of S segment is less than half of the L segment, the proportion of LASVs with S recombinants is significantly higher than that with L recombinants. These results suggest that HR may be a feature of LASV, which can be set by natural selection to produce beneficial or eliminate harmful mutations for the virus, so it plays a role in LASV evolution during the outbreak of LF.