Thank you everyone that has posted.
My personal belief is that by partaking of the fruit, which violated the commandment of God in the statement:
Genesis 2:16-1816 And the LORD God commanded the man, saying, Of every tree of the garden thou mayest freely eat:
17 But of the tree of the knowledge of good and evil, thou shalt not eat of it: for in the day that thou eatest thereof thou shalt surely die.
Adam and Eve transgressed. I believe that this made man capable of sin by giving man the knowledge of good and evil. Before that he did not know better. So man entered a state where evil was possible for him because he now had knowledge of good and evil. I do not believe in original sin.
Mormons believe that until the age of eight parents are responsible for teaching their children to choose "good" over "evil." By the age of eight a child should have learned enough to make decisions about right and wrong, given proper parental instruction. As such at eight we believe baptism should occur, this to wash away the sins committed in ignorance as they learned. Although a child younger than eight would not be held accountable for those sins, his/her parents would be. The verses I believe support the age are:
1 Peter 3:20-21
20 Which sometime were disobedient, when once the longsuffering of God waited in the days of Noah, while the ark was a preparing, wherein few, that is, eight souls were saved by water.
21 The like figure whereunto even baptism doth also now save us (not the putting away of the filth of the flesh, but the answer of a good conscience toward God,) by the resurrection of Jesus Christ:
The term figure I believe refers to the number. Which could also refer to a time frame other than eight years (i.e. days could be an interpretation, but I do not believe an eight day old would be able to show "good conscience toward God" and so infant baptism does not seem to fit this requirement.) This reference and interpretation is solely based on my readings, and is not LDS church doctrine, I have never heard such spoken anywhere.
I am not arguing the point merely stating my opinion, I hope that people will argue the point, I always find it interesting, but to tell the truth I do not know of Biblical verses that necessarily contradict the original sin concept, and don't really feel like researching it at the moment. I would like to hear the verses if Peejayd has them to support a stance against original sin. If the argument comes up at some other time it would be nice to know the references.
Alliance, you are right, I did have my answer to the question. I did pose the question only with the intent to learn the reason they believed this, and to see if there was any support for the concept since I knew of none. I had hoped there would be more debate on the subject, but I myself am ill equipped to debate the concept.