Fertility in the aging male: molecular pathways in the anthropology of aging.

The aging process is a normal stage in development characterized by the gradual deterioration of all life functions. As far as reproduction is concerned, aging is characterized by a significant limitation of fertility in both sexes. This process is, at least partially, attributed to the action (or loss of action) of sex steroids, coinciding with low activity of the pituitary-gonad axis. From an anthropological point of view, the study of reproductive aging is a unique opportunity to investigate various environmental and endogenous factors influencing sexual behavior and, thus, playing a significant role in human biology. Various techniques are now widely available to allow the detailed examination of reproductive hazards using only minor samples of genetic material. These methods are highly sensitive and specific and allow the characterization of distortions at subcellular and even molecular level. This short review briefly summarizes the current understanding of reproductive aging, as well as its potential clinical and anthropological impact.