All of your biologic samples will be under the control of the principal investigator of this research project. To protect your confidentiality, all personal identifiers (i.e., name, social security number, and birth date) will be removed (de-identified) and replaced with a specific code number. The information linking these code numbers to the corresponding subjects' identities will be kept in a separate, secure location. The investigators on this study will keep the samples indefinitely. Samples will be kept in the investigator's laboratory located in Scaife Hall, room 812, 3500 Terrace Street. You may request to have your samples destroyed if you withdraw. The request must be in writing and samples collected and not already processed will be destroyed.