Until then , early evidence in support of the existence of MAIS was limited to cases involving a mild defect in virilization .
Some of these early cases made allowances for some degree of impairment of genital masculinization .
Until then , early evidence in support of the existence of MAIS was limited to cases involving a mild defect in virilization , although some of these early cases made allowances for some degree of impairment of genital masculinization .