Mississippi Code Title 41. Public Health § 41-39-9

It is hereby declared lawful for any person eighteen (18) years of age and over, having a sound and disposing mind, to enter into a written contract with a qualified hospital or medical school to donate his eyes, heart, kidney or other transplantable part of a human body to medical science or for medical purposes. Any contract entered into under the terms of this section is hereby declared to be binding upon the surviving spouse or other heirs of the deceased who have the right under general law to claim his body.

Any person entering into such a contract may, during his or her lifetime, revoke by a written instrument, signed by both parties, said contract in its entirety. However, if any such person has received any monetary consideration for entering into said written contract, he or she upon revoking said contract shall repay such monetary consideration to those from whom he or she received the consideration, in full, plus six percent (6%) interest from the date of the signing of the contract.