Spontaneous genetic damage in the tegu lizard (Tupinambismerianae): The effect of age

SCHAUMBURG, LAURA G.; POLETTA, GISELA L.; SIROSKI, PABLO A.; MUDRY, MARTA D.

MUTATION RESEARCH. GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2014 vol. 766 p. 5 - 9

1383-5718

Several studies indicate that certain factors such as age, sex or nutritional status among others, may affect the level of DNA damage, both induced and spontaneous, so it is very important to consider them for a more accurate interpretation of the findings. The aim of this study was to analyze the influence of age, sex, and nest of origin on spontaneous genetic damage of Tupinambis merianae determined by the comet assay (CA) and the micronucleus (MN) test, in order to improve reference data for future in vivo studies of xenobiotics exposure in this species. Sixty-five tegu lizards of three different ages:newborns (NB), juveniles (JUV) and adults (AD), both sexes and from different nests of origin were used.Blood samples were collected from the caudal vein of all animals and the MN test and CA were applied on peripheral blood erythrocytes to determine basal frequency of MN (BFMN) and basal damage index(BDI). The comparison between age groups showed statistically significant differences in the BFMN and BDI (p < 0.05). NB animals showed significantly higher BDI values in relation to JUV and AD (p < 0.016), but no statistically differences were found between the latter two. NB showed lower BFMN respect to other age groups, being statistically significant only when compared to AD (p < 0.016). BFMN or BDI showed no statistically significant differences between sexes or nests of origin (p > 0.05). A weak negative relationship was found only between BFMN and weight of NB tegu lizard (p = 0.014; R2= 0.245). Basal values of genetic damage obtained with both biomarkers in the tegu lizard evidenced that age is an intrinsic factor that should be taken into account to avoid misunderstanding of the results in future biomonitoring studies.