Cytogenetic variability of lymphocytes from phenotypically normal men: influence of age, smoking, season, and sample storage.

A cytogenetic study was conducted on cultured lymphocytes from a group of 60 male volunteers to determine the baseline of chromosomal aberrations in nonchemical workers. Only males were included in the study to avoid any sex effects on the results. Blood samples were collected from each man every 13 w (quarterly) over a period of 12 m. A single batch of culture medium was used for the entire study. The influence of storing the blood samples prior to culture, donor's age, cigarette smoking, and seasonal variation on lymphocyte mitotic index and chromosomal aberration yield was analyzed. A significant decrease in mitotic activity was observed in cultures from samples stored for 3 d at room temperature (22 +/- 1 degree C). Storing of samples at refrigerator temperature (4 +/- 1 degree C) for up to 3 d prior to culture did not affect lymphocyte growth. Although the mitotic index was found to be inversely proportional to the age of the donors, a significant influence of age on total cytogenetic aberrations was not detectable. A group of 15 smokers appeared to have higher number of chromosomal aberrations; however, the difference in mean mitotic activity between lymphocytes of the two groups was not statistically significant. No detectable seasonal influence was found on any chromosomal aberration category except in the number of chromatid gaps. The mitotic indices of the first quarter cultures, on the other hand, showed significant differences from the other three quarters. The chromosomal aberration baseline of the group was not strikingly different from the ones reported by other investigators.(ABSTRACT TRUNCATED AT 250 WORDS)