[Theology] Original Sin in the Bible

"The first mention of the concept of Original Sin is found, not in Genesis, where the fatal event was supposed to happen, but in the fifth chapter of Romans, written by Paul. According to Paul, humanity was cursed because Adam sinned when he ate of the Tree of the Knowledge of Good and Evil.

[...]

At no point [in Genesis 3:14-19] do we see anything that might qualify as a curse of "Original Sin" to be handed down to all of Adam's descendants. Sure, their lives are supposed to become much more difficult than what they had heretofore experienced; but where in all of that is the "Sin" being passed along?

[...]

The rest of the Old Testament is of no help to Christian theology in this area: from this point in Genesis all of the way through the ending of Malachi, there isn't the slightest hint of there being any sort of Original Sin inherited by all humans through Adam. There are plenty of stories of God getting angry at humanity in general and at the Jews in particular, thus offering many opportunities for God to point out how everyone is "sinful" because of Adam. Yet we read nothing about that."

Atheism.about.com, May 5, 2007