Genetic variation in the CYP1A gene caused by laboratory exposure of benzo (a) pyrene to common carp

Abstract

Polycyclic aromatic hydrocarbons (PAHs) are pervasive environmental contaminants, with benzo(a)pyrene (B(a)P) standing out as a prototypical example. B(a)P is a known mutagen and carcinogen that, upon metabolic activation stimulated by cytochromes P450 (CYP1A) with microsomal epoxide hydrolase, reacts with DNA. In this study, common carp (Cyprinus carpio) were subjected to three different doses of B(a)P (1μg/kg and 10μg/kg) to investigate the mutagenic effects on B(a)P-derived DNA in vivo.Blood samples were collected, followed by thorough DNA extraction and polymerase chain reaction analysis. The findings revealed a pronounced mutational impact of B(a)P on the amplified segment of the CYP1A gene. Specifically, at a concentration of 1μg/kg, B(a)P induced 8 mutations, 3 amino acid alterations, and the emergence of 5 new haplotype patterns. In contrast, at a concentration of 10μg/kg, B(a)P resulted in 21 mutations, 10 changes in amino acids, and the generation of 7 new haplotype patterns. Additionally, alterations in the three-dimensional protein composition were observed in both dosage groups.This study underscores the significant mutagenic potential of B(a)P, shedding light on its capacity to induce genetic changes and protein structure modifications, thereby emphasizing the importance of monitoring and addressing the environmental presence of PAHs for both ecological and human health considerations