Tackling DNA data-sharing challenges

Inherited and unchanging throughout life, DNA is a powerful metric for identifying human remains. Technical improvements in using it have advanced over the decades; however, ethical, administrative and bureaucratic barriers restrict its use, particularly for transnational identification. This is apparent in US border states, where unidentified human remains (UHR) thought to be those of migrants are buried without DNA sampling or left to languish unnamed for years. Since 2008, over 800 UHR have been found in Brooks County, over 70 miles north of the Texas border with Mexico.1 Such unexplained deaths are subject to investigation which in most places includes an autopsy with DNA sampling; in South Texas, however, the relevant laws and practices were not followed prior to 2013, meaning that DNA samples were not taken. Graves are now being exhumed to collect DNA and other anthropological data to investigate the identities of the deceased. So far, 34 of 163 long-term deceased have been identified and more graves await exhumation. Due to the historic lack of case tracking in the region, we do not know how many more nameless or unmarked graves might contain the remains of missing people.2 Identification often takes years. Usually, UHR are sent to a medico-legal authority for identification where, in most cases, an autopsy will be performed, including DNA sampling. DNA data can be uploaded to the federal DNA data system, the Combined DNA Index System (CODIS). These data will be compared with the missing persons index and with an index of relatives of missing persons. The theory of DNA-based identification via CODIS is that at some point family members will report the missing person and provide ‘family reference’ DNA samples (FRS). Any jurisdiction in the US can take a missing person report and an FRS, then submit that FRS to a CODIS DNA laboratory.