Sperm Chromatin Condensation

Sperm chromatin becomes highly condensed during spermiogenesis due to the replacement of nucleosomal histones by intermediate proteins and protamines. Data suggests a potential role for sperm chromatin structure for the maintenance of proper epigenetic patterns during spermatogenesis. Additionally, this step of sperm chromatin condensation (SCC) is essential for paternal genome reprograming that helps expression of the appropriate genes during early embryo development. Therefore, a correct SCC plays a crucial role in the fertilizing capacity of males. Abnormalities of SCC have been correlated with poor sperm quality and reproductive outcomes. However, the mechanisms of defective SCC and the etiological factors underlying these defects are not fully understood. Additionally, tests evaluating SCC are not standardized and clinical guidance of their utility is lacking. In this chapter, we briefly discuss the physiological aspects of SCC and highlight its significance for natural fertility of men. We also discuss the etiopathogenesis of sperm chromatin abnormalities and explain their relevance in the context of infertility. Additionally, we describe the current methods for assessment of sperm chromatin integrity. Furthermore, we highlight the potential role of sperm chromatin testing in the management of couples undergoing assisted reproductive techniques.