Was the Virgin a myth that came from older cultures?

The myth of the hero born of a virginal conception not only occurs in Christianity, we can also find it in the Greco-Roman world. It is also something that we can observe in Egyptian stories. For example, the son Isis and Osiris who will incarnate in the pharaoh is conceived when Osiris has already passed away. Therefore, the idea that the mother of a Messiah, king or savior conceives him in a virginal way can be inspired by other religions.