The authors analyze literature data concerning high correlation between high intelligence and high testosterone level in amniotic liquid in case of mono-zygotic male-twins pregnancy. They have put the hypothesis of biological conditioning of intellectual gift in monozygotic male-twins. Their own new experimental data as well as results of other investigators made them assume that high involvement of right frontal cortex area in the current informational processing may serve as physiological marker of intellectual gift. Prenatal development peculiarities and psycho-social factors of postnatal twins development are discussed as the reasons of phenomenological absence of talented male-twins in human history.