CRISP2 and Infertility: -detected in testis, epididymal sperm and ejaculated spermatozoa-specifically regulates calcium flow through ryanodine receptors-is implicated in cell–cell adhesion and is capable of steroid binding-decreases in CRISP2 content in sperm is associated with infertility in humans and horses-its content is low in the epididymal sperm of very young and senile dogs