The data flow also went the other way.

Chinese government researchers contributed the data of 2,143 Uighurs to the Allele Frequency Database, an online search platform run by Dr. Kidd that was partly funded by the United States Department of Justice until last year. The database, known as Alfred, contains DNA data from more than 700 populations around the world.

This sharing of data could violate scientific norms of informed consent because it is not clear whether the Uighurs volunteered their DNA samples to the Chinese authorities, said Arthur Caplan, the founding head of the division of medical ethics at New York University’s School of Medicine. He said that “no one should be in a database without express consent.”

“Honestly, there’s been a kind of naïveté on the part of American scientists presuming that other people will follow the same rules and standards wherever they come from,” Dr. Caplan said.

Dr. Kidd said he was “not particularly happy” that the ministry had cited him in its patents, saying his data shouldn’t be used in ways that could allow people or institutions to potentially profit from it. If the Chinese authorities used data they got from their earlier collaborations with him, he added, there is little he can do to stop them.

He said he was unaware of the filings until he was contacted by The Times.

Dr. Kidd also said he considered his collaboration with the ministry to be no different from his work with police and forensics labs elsewhere. He said governments should have access to data about minorities, not just the dominant ethnic group, in order to have an accurate picture of the whole population.

As for the consent issue, he said the burden of meeting that standard lay with the Chinese researchers, though he said reports about what Uighurs are subjected to in China raised some difficult questions.

“I would assume they had appropriate informed consent on the samples,” he said, “though I must say what I’ve been hearing in the news recently about the treatment of the Uighurs raises concerns.”