NPR reports on the upcoming documentary, and the claim of Christopher Columbus's origins with this quote:
Broadcast by Spanish national public network RTVE on Oct. 12, the day of Spain’s national holiday marking the arrival of Columbus’ expedition to the Americas, Colón ADN, su verdadero origen, or “Columbus’ DNA, his true origin,” follows forensic medical expert José Antonio Lorente as he studies multiple hypotheses regarding the origin of the famed explorer and contrasts the information with scientific and historical evidence.
The documentary concludes that the most plausible theory is one maintained by a Catalan architect who has dedicated many years trying to demonstrate that Cristóbal Colón — Columbus’ name in Spanish — was a Jewish man from the region of Valencia, on the Mediterranean coast of eastern Spain.
Some in the scientific community, however, have expressed skepticism about the methods and scientific rigor that Lorente employs, and highlight the fact that Lorente’s findings have not been presented for peer review yet.
The article goes on to say that many in the scientific community, find Lorente's methods unreliable. It is not certain that the body that is claimed to be Christopher Columbus was actually his. Lorente has used DNA from Columbus's son and distant cousin to corrobate that it is his body.
NPR cites the Spanish newspaper El País claiming that proving this via DNA is nearly impossible. The documentarian is not answering questions about his work at this time. Lorente himself admits the DNA he could get, was highly degraded.