According to Donna J. Haraway's latest book, gender is never something one possesses, like an arm, haircolor, or strength:
Gender is always a relationship, not a preformed category of beings or a possession that one can have. Gender does not pertain more to women than to men. Gender is the relation between variously constituted categories of men and women (and variously arrayed tropes), differentiated by nation, generation, class, lineage, color, and much else. 
Gender and race have never existed separately and never were about preformed subjects endowed with funny genitals and curious colors. Race and gender are about entwined, barely analytically separable, highly protean, relational categories. Racial, class, sexual, and gender formations (not essences) were, from the start, dangerous and rickety machines for guarding the chief fictions and powers of European civil manhood. To be unmanly is to be uncivil, to be dark is to be unruly: These metaphors have mattered enormously in the constitution of what may count as knowledge. 
Donna J. Haraway, Modest_Witness@Second_Millennium. FemaleManŠ_Meets_OncoMouse: Feminism and Technoscience. New York and London: Routledge, 1997.