Ranking of the housekeeping genes in desert locust brain tissues of L5 and adult specimens. Gene expression stability of the housekeeping genes by (A) geNorm and (B) Normfinder in desert locust brain tissues of L5 and adult specimens. (A) geNorm gives an average expression stability measure (AESM) as the mean of the stability values of the remaining genes in a stepwise exclusion process. The lower the AESM, the more stable the gene in the subset. The threshold for an unstable gene is M ≥5 1. 5 (B) Normfinder calculates a stability value which is also inversely proportional to the stability of the gene in under study.