The Lock-and-Key Mechanism of Ovum-Led Sex Determination: A Gamete Selection Hypothesis and Experimental Protocol

Conventional paradigms in genetics and reproductive demography assume that human sex determination is dictated unilaterally by male sperm chromosome segregation. Building upon our earlier statistical framework of gamete selection, this paper presents a novel molecular physiological hypothesis: the Lock-and-Key Mechanism of Ovum-Led Sex Determination. We assert that the human ovum acts as an active controller rather than a passive recipient. Specific surface receptors and follicular fluid microenvironments establish selective lock states (X-lock or Y-lock) that grant entry strictly to matching sperm keys. Under stable maternal physiological conditions, this mechanism accounts for localized deviations from standard binomial distributions. Crucially, we propose a rigorous, quantitative mouse in vitro fertilization (IVF) protocol to empirically test this model, predicting a 50% fertilization reduction in pure-sperm cohorts.