Isoenzymes of human lice: Pediculus humanus and P-capitis

Human lice (Phthiraptera: Pediculidae) from Africa, America and Europe were electrophoresed for 28 enzymes, with special interest in metabolic factors likely to be involved with insecticide resistance. Zymogram profiles of th e body louse (Pediculus humanus L. from France and U.S.A.) and the head lou se (P. capitis DeGeer from France, Madagascar, Mali & Senegal) were compare d. Only two enzymes, phosphoglucomutase (Pgm) and esterase 3 (Est-3), showe d electrophoretic variation. In our starch gel electrophoresis conditions, P. humanus showed three electromorphs of Pgm migrating anodally 6, 11 and 1 6 mm (designated alleles a, b, c, respectively). Of the putative Pgm allele s, b and c occurred in all samples of both species of lice, whereas allele a was found only in P. humanus lab strain from U.S.A. Esterase 3 had four e lectromorphs migrating 23, 26, 30 and 35 mm (designated alleles a, b, c and d). Among putative Est alleles, a was found only in P. capitis from Bamako (all 14 specimens aa homozygotes), allele d was found only in P. capitis f rom Dakar (39% frequency), whereas Est-3 alleles b and c showed apparently balanced polymorphism in all samples of both P. humanus and P. capitis exce pt that from Bamako. Despite the limited amount of isoenzyme variation dete cted (only 2/31 polymorphic loci), divergences of Est-3 and Pgm among Pedic ulus populations may be relevant to their biosystematics and resistance.