her sister in thePrologue that she is going to bury their brother.

ISOMENE Our own death would be if we should go against Creon...
                                                               ....We are only women,
                We cannot fight with men, Antigone!
                The law is strong, we must give in to the law....(46-48)

ANTIGONE                          You may do as you like,
                 Since apparently the laws of the gods mean nothing to you (60-61)

This open defiance of Antigone's, who apparently has not petitioned Creon for her brother's body before his decree in Scene I, challenges the authority of King Creon, thereby placing Antigone quickly in a vulnerable position, especially as a woman.

Then, in Scene II when she is brought before Creon by the sentry who has caught her as she tries to bury Polyneices, Antigone is dangerously defiant. As Creon asks her if she has heard his proclamation, Antigone replies with impudence,

ANTIGONE  It was public. Could I help hearing it?
CREON       And yet you dared defy the law.
ANTIGONE  ...It was not God's proclamation. That final justice
                 That rules the world below makes no such laws....
                 But all your strength is weakness itself against
                 The immortal unrecorded laws of God. 
                 They are not merely now: they were, and shall be,
                 Operative forever, beyond man utterly. (55-64)

This public affront to Creon, were it even made by a man, would be highly insulting. But, such an challenge to his authority made by a woman, clearly places Antigone in a most dangerous position because the proud Creon, then, feels that he must assert his authority. 

This defiance of Antigone is what defines tragedy, as tragic figures often struggle against authority. Clearly, Antigone sets herself against a force who is more powerful than she. Moreover, her being a woman adds to the insults that King Creon feels; thus, he becomes determined to not be undone by a woman. In Scene III, when Antigone's betrothed Haemon, the son of Creon, comes to his father on Antigone's behalf, he tells his son that men are the lawmakers  

CREON And no woman shall seduce us. If we must lose,
           Let's lose to a man, at least! Is a woman stronger than we? (48)

Antigone's defiance against Creon challenges not just his authority as king, it also challenges his manhood, and he vows not to be defied by her.

Gender does influence both Antigone's actions and the way that Creon reacted to them. 

First, women were responsible for many aspects of funeral rites, tending graves, and mourning in ancient Greek society. Thus Antigone's sense of responsibility for burying her brother had to do with it being a specifically feminine duty. Defying the edict of Creon, though, was rather atypical for a Greek woman, as the ideal of womanhood in the period involved submission and women were legally under the control of their fathers or male guardians. 

Creon's walling Antigone up in a cave rather than killing her outright was in part due to her gender and in part due to a worry that killing one's own kin would bring down ritual pollution and the consequent vengeance of the gods, as it had done in the case of Oedipus' killing of Laius.