Sir

Even though the controversial withdrawal of a paper on the genetic relatedness of Palestinians and Jews by the journal Human Immunology (see Nature 414, 382; 2001) is a minor episode compared with the tragedies caused by ethnic/religious conflicts over past decades, the issues involved are worth revisiting.

The stated purpose of the paper by Antonio Arnaiz-Villena et al. was to “examine the genetic relationships between the Palestinians and their neighbours (particularly the Jews) in order to: (1) discover the Palestinian origins, and (2) explain the historic basis of the present ... conflict between Palestinians and other Muslim countries with Israelite Jews”.

They conclude: “Jews and Palestinians share a very similar HLA genetic pool that supports a common ancient Canaanite origin. Therefore, the origin of the long-lasting Jewish–Palestinian hostility is the fight for land in ancient times.”

It is difficult to believe that knowledge of genes may help to explain the present conflict. Although population genetics can address issues of relatedness of populations, mating patterns, migrations and so on, obviously it cannot provide evidence about reasons for conflicts between people.

Our primary concern, however, is that the authors might be perceived to have been discriminated against for political, as opposed to legitimate scientific, reasons.

Even a cursory look at the paper's diagrams and trees immediately indicates that the authors make some extraordinary claims. They used a single genetic marker, HLA DRB1, for their analysis to construct a genealogical tree and map of 28 populations from Europe, the Middle East, Africa and Japan. Using results from the analysis of a single marker, particularly one likely to have undergone selection, for the purpose of reconstructing genealogies is unreliable and unacceptable practice in population genetics.

The limitations are made evident by the authors' extraordinary observations that Greeks are very similar to Ethiopians and east Africans but very distant from other south Europeans; and that the Japanese are nearly identical to west and south Africans. It is surprising that the authors were not puzzled by these anomalous results, which contradict history, geography, anthropology and all prior population-genetic studies of these groups. Surely the ordinary process of refereeing would have saved the field from this dispute.

We believe that the paper should have been refused for publication on the simple grounds that it lacked scientific merit.