The question asks whether the researchers are obligated to recontact the participants for their consent before doing a genetic analysis on the specimens donated by the participants for the previous study. Thus, the primary work on the study is probably completed, but the samples are still in the freezer. That does not seem to have been the case here, and probably was not required for most older studies. The fate of the data and specimens should be a concern of all researchers carrying out research using human subjects. After all, scientists are trained to keep samples just in case something comes up in the future such as a question about the previous work, or an opportunity to extend the investigation previously conducted.
Most scientists have freezers and storage cabinets bulging with materials from earlier research.
In this case, it is important to note that those 10,000 blood samples that Smith has in her freezer are not the same as the thousands of slices from a sediment core drilled out of a lake bed that a geologist across campus may have carefully stored in her cabinet. Smith's samples come from human beings, and therefore the issues of resect for persons and confidentiality need to be considered as well as scientific merit when new analyses are contemplated. The women who participated in the study have a right to have a say in what is done with these specimens taken from their bodies. This definition emphasizes that these research materials are different from others scientists may use in their work, like the sediment core noted above, and that these samples must be treated with respect. The concept of respect for persons comes largely out of the writings of Immanuel Kant who asserted that one should Act so that you treat humanity, whether in your own person or in that of another, always as an end and never as a means only.