The Yanomami live thousands of miles away from us and are a part of a completely different cultural society. They don't live in a society like ours in which there has been such a rapid development in technology and constant diversification. I believe it is the duty of powerful countries, like our own, to help third world countries in their struggle for fighting off disease and getting back what is rightly theirs.
The Yanomami culture and lifestyle was once unknown to Americans, but they were generous and trusted us enough to welcome us into their life so we could get a better perspective of their culture and traditions. When a village which is miles away from any sort of western influence or modernized society can be open enough to allow strangers to come in and watch their every move we must be appreciative about that. It is with their courteousness that early anthropologists and scholars were able to study the Yanomami and in turn have successful careers. Anthropology students and the alike have and still are learning so much from the Yanomami and other such cultural groups that we have a certain obligation to do something for them in return.
Being professionals, when one makes a promise to help gain more knowledge in preventing something like a disease it is their duty to pull through and fulfill that promise. Especially since it was these professionals who went to the Amazon and said they were willing to help themselves. The Yanomami were promised to be helped and if this promise cannot be fulfilled then the blood samples should be given back or the Yanomami may lose faith in people who try to help them in the future. They welcomed the professionals into their world with open arms so the professionals in turn should respect their feelings and give back the blood samples.
The Yanomami aren't asking for the blood samples back for any selfish reasons, but because it is related to their religious beliefs. In the Yanomami culture it is believed that if all parts of a deceased Yanomami aren't deposed then they may get mad and will not be able to leave the world in peace, which can have negative consequences for the living and cause them harm. There must be cultural humility when dealing with different cultures; everyone has different beliefs and rituals and we must respect them. Every culture is different and their needs to be respect even if their practices are completely different from our own.
It might've been understandable if returning the blood samples would be hazardous, but as proved by The Federal University of the State of Para they were able to medically transfer the blood samples to Roraima with the proper medical cautions. The Yanomami had no medical problems with handling these samples that were returned. The claim of not sending the samples back because of danger has been proven not to be valid by this point, so they should be returned. Especially since the Yanomami will ceremonially destroy the blood samples on their return; there will be very minimum contact with the samples which in turn means an extremely low chance of disease transmission.
The Yanomami live in an isolated region and have no way of having their voice heard; it is our duty to let their voices be heard and give them a fighting chance. They were promised to receive information regarding a disease that is devastating their society with the use of their ancestor's blood samples. Never receiving any kind of information nor getting their blood samples back is betrayal from a professional institute, which not only makes them look bad but also puts a blemish on our society as a whole.