Imidacloprid and thiamethoxam induced mutations in internal transcribed spacer 2 (ITS2) of Anopheles stephensi

Abstract

The present article deals with the polymerase chain reaction (PCR)-based genotoxicity evaluation of neonicotinoid pesticides, imidacloprid and thiamethoxam, by using the genome of a mosquito Anopheles stephensi taken as an experimental model. After treatment of the second instar larvae with LC20 of the pesticides for 24 h, the induced nucleotide sequence variations in the internal transcribed spacer 2 (ITS2) of freshly hatched unfed control and treated individuals was studied from the sequence alignment data and the mutations in the form of insertion, deletion and substitution of bases were recorded. Measurable differences, indicative of the genetic damage due to imidacloprid and thiamethoxam were observed when ITS2 sequences of control and treated individuals were compared. It was found that imidacloprid-treated individual had 8 deletions, 29 insertions, 18 transitions and 33 transversions, whereas thiamethoxam-treated individual had 10 deletions, 8 insertions, 47 transitions and 68 transversions.

Thiamethoxam-induced hematological, biochemical, and genetic alterations and the ameliorated effect of Moringa oleifera in male mice

“…More recently, some hematobiochemical studies confirmed that anemia and alterations of liver and kidney biomarkers were reliable findings in TMX treated cockerels [ 8 ], birds [ [9] , [10] , [11] ], fish [ 12 , 13 ], and rats [ [14] , [15] , [16] ]. Besides, the mutagenic effect of TMX has been demonstrated in many studies [ 17 , 18 ].…”

Intragenomic sequence variations in the second internal transcribed spacer (ITS2) ribosomal DNA of the malaria vector Anopheles stephensi

“…stephensi , numerous ITS2 sequences are available in the GenBank and research publications [ 2 , 8 , 10 , 26 – 28 ]. However, polymorphism in length and nucleotide sequence has been observed in sequences reported from Iran [ 26 ], India [ 28 ], and in several GenBank sequences. Such intraspecific polymorphism is intriguing.…”

Adulticidal & larvicidal efficacy of three neonicotinoids against insecticide susceptible & resistant mosquito strains

“…In another study the LC 50 against yellow fever mosquito was 0.03 mg/l for imidacloprid, 0.06 mg/l for acetamiprid and 0.007 mg/l for thiamethoxam and 0.11 mg/l for dinotefuran 15 . Bhinder et al 16 compared the toxicity of imidacloprid and thiamethoxam in An. stephensi Liston (Diptera: Culicidae) and noticed measurable differences in internal transcribed spacer 2 (ITS2) sequences of control and treated mosquitoes indicating genetic damage.…”