On 22 February 1498, a well-weathered mid-40s Christopher Columbus ordained in writing that his estate in the Italian port city of Genoa would be maintained for his family "because from it I came and in it I was born".

Though most historians regard the document to be a cut-and-dried record of the famed explorer's birthplace, some have questioned its authenticity and wondered if there's more to the story.

A decades-long investigation led by forensics scientist José Antonio Lorente from the University of Granada in Spain has now come out in support of claims that Columbus may not be of Italian heritage after all, but was actually born somewhere in Spain to parents of Jewish ancestry.

The revelation was announced as part of a special program broadcast in Spain to celebrate Columbus's arrival in the New World on 12 October 1492.

It's important to keep in mind that science by media ought to be viewed with caution, especially when there isn't a peer-reviewed publication to critically examine.

"Unfortunately, from a scientific point of view, we can't really evaluate what was in the documentary because they offered no data from the analysis whatsoever," former director of Spain's National Institute of Toxicology and Forensic Sciences, Antonio Alonso, told Manuel Ansede and Nuño Domínguez at the Spanish news service, El País.

"My conclusion is that the documentary never shows Columbus's DNA and, as scientists, we don't know what analysis was undertaken."

Nonetheless, historical documents are increasingly being challenged – and bolstered – by forensic analyses of biological records, raising the possibility that Columbus's own DNA could potentially reveal insights into his family history.

Based on interpretations of records written when he was an adult, the man known throughout much of the western world by the anglicized name Christopher Columbus was born Cristoforo Columbo sometime between late August and late October in 1451 in Genoa, the bustling capital of the northwestern Italian region of Liguria.

It was only later in life as a young man in his twenties that he traveled west to Lisbon, Portugal, in search of affluent patrons who might fund his audacious attempt to take a 'short cut' to the east by heading in completely the other direction.

Though most historians accept the court documents placing his birthplace in Genoa as the real-deal, speculation of an alternative heritage has been floated for decades.

One persistent rumor maintains Columbus was covertly Jewish, born in Spain at a time of intense religious persecution and ethnic cleansing. Supporters of the claim cite curious abnormalities in his will and interpretations of the syntax in his letters.

Now, it appears his own genes may provide a new line of evidence.

Lorente and his team of researchers claimed in the televised special that their analysis of Y chromosome and mitochondrial DNA taken from the remains of Columbus's son Ferdinand and brother Diego is compatible with a Spanish or Sephardim Jewish heritage.

This doesn't categorically rule out Genoa, of course, nor does it pin down any one place in Europe as a place of birth for the explorer. Indeed, Jews exiled from Spain at the end of the 15th century just as Columbus was making his landmark voyage flooded into the Italian city seeking asylum, albeit with few succeeding.

But any merit to Lorente's findings would make Columbus's Italian origin a little harder to support, raising questions of how somebody of Sephardim Jew heritage would come to be born in Genoa in the 1450s.

For the findings to become widely adopted, the results would need to be carefully scrutinized, if not convincingly replicated in detail.

Even then, there's more to an individual's story than genetics – leaving open the case of how an individual from a persecuted minority truly came to represent the spearhead of Spanish expansion.

For now, the story of Columbus remains one of an Italian sailor who caught the eye of Spanish royalty, who came to be both celebrated and scorned for the mark he inadvertently made on history far from that "noble and powerful city by the sea", his home of Genoa.