Exposure to oxychlordane is associated with shorter telomeres in arctic breeding kittiwakes

Abstract

Telomeres are DNA-protein complexes located at the end of chromosomes, which play an important role in maintaining the genomic integrity. Telomeres shorten at each cell division and previous studies have shown that telomere length is related to health and lifespan and can be affected by a wide range of environmental factors. Among them, some persistent organic pollutants (POPs) have the potential to damage DNA. However, the effect of POPs on telomeres is poorly known for wildlife. Here, we investigated the relationships between some legacy POPs (organochlorine pesticides and polychlorobiphenyls) and telomere length in breeding adult black-legged kittiwakes (Rissa tridactyla), an arctic seabird species. Our results show that among legacy POPs, only blood concentration of oxychlordane, the major metabolite of chlordane mixture, is associated with shorter telomere length in females but not in males. This suggests that female kittiwakes could be more sensitive to oxychlordane, potentially explaining the previously reported lower survival rate in most oxychlordane-contaminated kittiwakes from the same population. This study is the first to report a significant and negative relationship between POPs and telomere length in a free-living bird and highlights sex-related susceptibility to banned pesticides.

Somatic growth and telomere dynamics in vertebrates: relationships, mechanisms and consequences

“…However, the variation in pollutant levels might well be correlated with other lifestyle factors that have induced differences in telomere loss. Similarly, levels of oxychlordane circulating in the blood of a long-lived seabird, the kittiwake Rissa tridactyla, were found to be negatively related to red blood cell telomere length in female birds [50]. Particularly interesting in this kittiwake study is that no relationship was found in the male birds, despite the plasma levels of pesticides being similar in both sexes.…”

Corticosterone, inflammation, immune status and telomere length in frigatebird nestlings facing a severe herpesvirus infection

“…Determination of telomere length was performed at the Centre d'Etudes Biologiques de Chizé (CEBC) by Southern blot using the TeloTAGGG Telomere Length Assay (Roche, Mannheim, Germany) as previously described (Blévin et al ., 2016). After digestion with proteinase K and DNA extraction from red blood cells using the DNeasy blood and tissue kit (Qiagen), DNA quality was carefully checked before telomere analyses (Nussey et al ., 2014).…”

DNA damage in Arctic seabirds: Baseline, sensitivity to a genotoxic stressor, and association with organohalogen contaminants

“…Deoxyribonucleic acid (DNA) strand breakage is a promising biomarker of contaminant exposure and effect because DNA integrity and maintenance is vital for cellular and tissue function [6]. Several contaminants are known genotoxicants because they can affect genome integrity by adduct formation, production of reactive oxygen species, strand breaks, and impairment of DNA repair mechanisms [7][8][9]. Double-strand breaks represent a severe type of DNA lesion, because the continuity of the DNA molecule is potentially disrupted.…”