Boosting life sciences research in Brazil: building a case for a local Drosophila stock center

Abstract

Drosophila melanogaster is undoubtedly one of the most useful model organisms in biology. Initially used in solidifying the principles of heredity, and establishing the basic concepts of population genetics and of the synthetic theory of evolution, it can currently offer scientists much more: the possibility of investigating a plethora of cellular and biological mechanisms, from development and function of the immune system to animal neurogenesis, tumorigenesis and beyond. Extensive resources are available for the community of Drosophila researchers worldwide, including an ever-growing number of mutant, transgenic and genomically-edited lines currently carried by stock centers in North America, Europe and Asia. Here, we provide evidence for the importance of stock centers in sustaining the substantial increase in the output of Drosophila research worldwide in recent decades. We also discuss the challenges that Brazilian Drosophila scientists face to keep their research projects internationally competitive, and argue that difficulties in importing fly lines from international stock centers have significantly stalled the progression of all Drosophila research areas in the country. Establishing a local stock center might be the first step towards building a strong local Drosophila community that will likely contribute to all areas of life sciences research.

Figure 1 -. The historical increase in worldwide Drosophila publications is associated with the increased capacity of the BDSC to distribute its stocks. The number of publications trendline was constructed based on a search of the Scopus databank using the query “TITLE-ABS-KEY (Drosophila)”. A change in slope of this trendline can be seen after the late 1980s/early 1990s (from 1960 to 1986, linear equation y = 35.99x - 70464, R² = 0.98; from 1987 to 2003, linear equation y = 191.09x - 378764, R² = 0.99). See Supplementary Table S1 for raw data. The trendlines of the number of stocks carried and of stocks distributed worldwide by the BDSC were constructed based on the information available at https://bdsc.indiana.edu/about/history.html. Because of the impact of the COVID-19 pandemic on research output, data from 2020-2023 was not included.

Figure 2 -. Limited BDSC stock distribution to Brazil and correlated Drosophila publications. The number of publications trendlines (A) were constructed based on a search of the Scopus databank using the queries “AFFILCOUNTRY (Brazil OR Argentina OR Colombia OR Peru OR Bolivia OR Chile OR Venezuela OR Paraguay OR Uruguay OR Ecuador) TITLE-ABS-KEY (Drosophila)”; “AFFILCOUNTRY (Brazil) TITLE-ABS-KEY (Drosophila)”; “AFFILCOUNTRY (Brazil OR Argentina OR Colombia OR Peru OR Bolivia OR Chile OR Venezuela OR Paraguay OR Uruguay OR Ecuador) TITLE-ABS-KEY (Drosophila AND evolution* OR population)”; and “AFFILCOUNTRY (Brazil) TITLE-ABS-KEY (Drosophila AND evolution* OR population). From 1990 on, linear equations for general Drosophila publications from South American and Brazilian only researchers were, respectively, y = 5.02x - 9981 (R² = 0.95) and y = 2.97x - 5909 (R² = 0.92). See Table S1 for raw data. The trendlines of the number of stocks distributed to South America and Brazil alone (B) were constructed based on the information made available by the BDSC to the authors. These numbers must be seen as approximations of the real number of stocks shipped to the continent due to four main reasons: 1) prior to 2011, BDSC occasionally reused account numbers, which may have produced confounding numbers; 2) the numbers do not include stocks that died en route and had to be reshipped; 3) the numbers reflect the current location of the primary BDSC account holder (the principal investigator), including from a time during which the account holder may have been based on a non-South American country; and 4) they include stocks shipped to non-South American countries, but which were ordered from a BDSC account for which the holder is based on a South American country. Because of the impact of the COVID-19 pandemic on research output, data from 2020-2023 was not included.

Figure 3 -. Limited output of Drosophila life sciences research from Brazil. A, The normalized trendlines for number of publications were constructed based on searches of the Scopus databank using the following queries: “TITLE-ABS-KEY (Drosophila AND mitochondr* AND metabolism)”; “TITLE-ABS-KEY (mitochondr* AND metabolism)”; “AFFILCOUNTRY (Brazil OR Argentina OR Colombia OR Peru OR Venezuela OR Chile OR Paraguay OR Uruguay OR Bolivia OR Ecuador) TITLE-ABS-KEY (mitochondr* AND metabolism)”; “AFFILCOUNTRY (Brazil) TITLE-ABS-KEY (mitochondr* AND metabolism)”; “AFFILCOUNTRY (Brazil OR Argentina OR Colombia OR Peru OR Venezuela OR Chile OR Paraguay OR Uruguay OR Bolivia OR Ecuador) TITLE-ABS-KEY (Drosophila AND mitochondr* AND metabolism)”; “AFFILCOUNTRY (Brazil) TITLE-ABS-KEY (Drosophila AND mitochondr* AND metabolism)”. The data was separately normalized by the highest yearly number of articles published, which was arbitrarily set to 1.0. See Table S1 for raw data. B-D, The trendlines were constructed similarly as in A, using queries in which the term “mitochondr* AND metabolism” was respectively replaced by “development* AND biology”, “neuro*” and “quantitative AND genetics”. Because of the impact of the COVID-19 pandemic on research output, data from 2020-2023 was not included.