Effect of endocrine disruptors on the ratio of X and Y chromosome-bearing live spermatozoa.

Highlights • EDCs tested have a negative impact on human sperm functions. • There are no significant differences in the viability of euploidy and aneuploidy spermatozoa following exposure to EDCs. • TCDD, DBCP, and Diaz adversely affect the viability of Y spermatozoa more than X spermatozoa. • A reduction in Y sperm viability may result in a female-biased sex ratio of offspring at birth. Abstract Although equal numbers of X and Y spermatozoa are produced during spermatogenesis, the sex chromosome ratio in ejaculated spermatozoa can be altered by exposure to endocrine-disrupting chemicals (EDCs), which can be reflected by altered sex ratios at birth. Here, we hypothesized EDCs affect sperm functions and viability of X and Y chromosome-bearing human spermatozoa. After exposure to genistein (Gen), bisphenol A (BPA), 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), dibromochloropropane (DBCP), and diazinon (Diaz), we evaluated motility, viability, capacitation, and differential viability of X and Y spermatozoa. All EDCs tested altered sperm viability, motility, and capacitation. Interestingly, the Y/X ratio of live spermatozoa was significantly lower in sperm treated with TCDD, DBCP, and Diaz than control spermatozoa. Our results suggest that some of EDCs have larger effects on the viability of Y spermatozoa than X spermatozoa, implicating that a reduction in Y sperm viability may result in a female-biased sex ratio of offspring at birth. [ABSTRACT FROM AUTHOR]