I read with great interest the recent official European Respiratory Society technical standard entitled "Global Lung Function Initiative reference values for static lung volumes in individuals of European ancestry" [1]. The manuscript is very interesting, and certainly it will mark the "history" of pulmonary function reference equations [2]. In the aforementioned study, 7190 observations from 17 centres were submitted and reference equations were derived for individuals aged 5 to 80 years [1]. The centres were based in 11 countries localised in four continents (Europe, Ocean, America and Africa). Since the vast majority (97.2%) of data came from individuals having a "European ancestry", this expression was used to "describe" the included individuals [1]. According to HALL et al. [1], the "European ancestry" was defined using the same classification as in the Global Lung Function Initiative (GLI-2012) spirometry analysis [3]. Since Tunisia (a North-African country) participated in the GLI-2021 study by contributing 615 data points (i.e. 8.55% of the total dataset), researchers may ask the following question: do Tunisians have a 100% European ancestry (as stated by HALL et al. [1] in their table 1)? According to the author, there is no "easy" and "affirmative" answer to this question, and it was interesting to discuss/highlight the above point as a study limitation [1].In a previous Tunisian study aiming to ascertain how well the GLI-2012 reference equations [3] fit adult Tunisian spirometric data, the authors clearly noted that "the populations of Tunisia are made-up of people of mainly Arab, Berber, and Turkish descent" [4]. Tunisians are mainly genetically descended from native Berber groups, with some Punic and Phoenician as well as Middle eastern input [5]. To a lesser degree, Tunisians are descended from other North-African and/or European peoples [5]. In brief, less than 20% of Tunisian global genetic material (Y-chromosome examination) comes from the present day Levant, Arabia, Europe or sub-Saharan Africa [6][7][8][9]. Therefore, the qualification of Tunisian participants as having a 100% European ancestry needs to be "discussed". In reality, the Tunisian genetic detachments to European samples are smaller than those to North-African groups. According to historical records, this could be explicated by the history of the Tunisian population, reflecting the effects of the earliest Punic colonists of Carthage succeeded, among others, by Roman, Byzantine, Arab and French occupations. Nevertheless, additional reasons cannot be rejected, such as the possibility of genetic drift, whose impact might be mainly bigger on the X chromosome [7,8]. This proposes a fairly significant European input to Tunisian genetics compared to other adjoining populations. For the above reasons, and as previously recommended for the GLI-2012 spirometric norms [3], considering Tunisian (and therefore North-African) populations as individuals of a "European ancestry" is a methodological limitation [1].To conclude, the statement that Tun...