Political and biological reality checks

One of the lectures I remember most clearly from an economic botany class at Yale University that I took more than 50 years ago was about vegetables in the family Cruciferae (now Brassicaceae). In that lecture, James Rodman, the professor, described the work of Georgii Karpechenko, a Soviet botanist who had hybridized two brassicaceous plants, Raphanus radishes and Brassica cabbage, to create a new genus, Raphanobrassica, through allopolyploidy (1). As described in my scribbled notes from the lecture, “One of the first intergeneric crosses made was in Cruciferae. Karpechenko crossed a cabbage (Brassica) and a radish (Raphanus) and called it Raphanobrassica. Unfortunately, it didn’t have an edible root and it didn’t have a leafy top. Economically zilch.” I only recently learned just how consequential Karpechenko's work on hybridization proved to be for him personally; after a dozen years of conducting hybridization studies, he was arrested on charges of anti-Soviet activity and executed.

May R. Berenbaum.

What sent me back to my old notes at this moment in time were recent news stories about political interference in scientific research. Karpechenko’s death is emblematic of the influence of Soviet agronomist Trofim Lysenko in political circles, who brought along with him in his rise to fame in the late 1930 s an enthusiastic embrace of a version of Lamarckism postulating hereditary transmission of acquired characteristics and a general disdain for classical Mendelian genetics as “bourgeois science” (2). Lysenko’s concept of evolution of acquired characteristics fit the needs of Russian agronomy at the beginning of the 20th century, a time of widespread crop failures and famines. Crop improvement by cross-breeding according to Mendelian principles would have been a slow and unpredictable process, particularly in the context of the instability of crop production characteristic of Russian agriculture at the time. Applying the process of vernalization, i.e., accelerating the germination of seeds by exposing them to extended cold conditions, Lysenko reported inducing winter seeds of wheat and other cereals to germinate in spring and argued that the changes induced environmentally, i.e., by chilling, could become heritable, or transmissible to future generations (3).

It’s unclear whether Lysenko’s work was carefully documented or even statistically analyzed—Borinskaya et al. (4) stated that he “denied statistics”—but his claims impressed Soviet politician Joseph Stalin, who aggressively promoted his work (5). Lysenko also routinely disparaged many of his scientific colleagues whose work he perceived as inconsistent with his own. In addition to criticizing their science, he also accused scientific opponents as being anti-Stalinists and “enemies of the people” (6). By 1940, Lysenko had been appointed as director of the Institute of Genetics of the Soviet Academy of Sciences. That year, the Russian plant geneticist Nicolai Vavilov, one of Lysenko’s most vocal opponents, objected to some of his political appointees and soon thereafter was arrested and sentenced to prison, where he ultimately died (7). Other Russian geneticists who were executed or sentenced to labor camps for scientific apostasy during this period included Gregory Levitsky, Izrail Agol, Solomon G. Levit, and Georgii Nadson (6, 8), among many others.

Lysenko’s career flourished and in 1943 he received the State Stalin Prize; two years later, he was awarded the Order of Lenin for aiding the effort to maintain food production during the war. Much of his extensive publication record appeared in Byulleten yarovizatsii, a journal he himself edited. Lysenko remained in his position at the Institute for another decade, but after the death of Stalin he eventually was denounced himself and in 1965 he was dismissed as director of the Institute of Genetics and reassigned to an experimental farm in the outskirts of Moscow. He died in 1976 and was memorialized in the New York Times with the note that, “In his position of scientific overlord, in the view of many, he caused lasting damage to Soviet biology and genetics by barring research along lines other than those he approved” (9).

Today, political interference with science isn’t as deadly as it was in twentieth century Russia, but it still presents challenges around the world. The National Academy of Sciences created its Committee on Human Rights (CHR) in 1976, to support colleagues who have been subjected to unfair trials, imprisonment, torture, and other forms of ill-treatment for their professional work or for speaking out on sensitive issues within their societies (10). Short of threats to life and limb, though, political interference also occurs when policies purported to be evidence-based are implemented absent documentation of any such evidence from credible sources. In my view, making a scientific argument, rather than a political, ideological, or moral argument, creates an obligation to use the standards and practices of science to do so.

The problem, though, is that there are limits even on evidence-based decision-making. Interpreting evidence, e.g., can be influenced by bias; as well, evidence itself is (or should be) in continuous flux. Even a biological “fact” as straightforward as the number of human chromosomes has changed over time. Gartler (11) provides a history of how determining that the correct typical human chromosome number, 46, was delayed for decades due to preconception: the number “was supposed to be 48 so subsequent investigators did everything possible to make their counts 48.”

Clearly, science cannot advance by never challenging longstanding consensus. It’s important to remember that “settled science” more than 230 years ago attributed a 1793 outbreak of yellow fever in Philadelphia that killed more than 5,000 people to a shipment of “putrid coffee” on board a ship arriving from Havana, Cuba (12, 13). Although bad smells and other forms of “miasma” have been blamed for disease outbreaks since the days of the ancient Greek physician Hippocrates, a far more likely explanation for the yellow fever outbreak was that Aedes aegypti yellow fever mosquitoes, which transmit the virus that causes yellow fever through feeding on human blood, very likely accompanied the ship that brought the coffee to Philadelphia from Havana, where a yellow fever epidemic was raging.

It was perhaps fortunate for the field of entomology that Lysenko for the most part didn’t concern himself with methods of controlling livestock pests, but in fact there was one exception where his rejection of classical genetics could have contributed to additional agricultural losses in Russia. The New World screwworm Cochliomyia hominivorax is a parasite of cattle and other mammals (including humans), the maggots of which burrow into the flesh of living hosts and have historically caused massive losses in livestock operations. A method known as autocidal control, or sterile insect release, was implemented in New World in the 1950s by Raymond Bushland and Edward Kipling. Knowing that female screwworm flies mate only once, Bushland and Knipling sterilized male flies by exposing them to X-rays and then released them in large numbers, increasing the likelihood that the females in the wild would mate with the laboratory-raised sterile flies, thereby interrupting the reproductive cycle. The method was field-tested and implemented widely with great success in Central and South America; by the 1990s, screwworm flies had been eradicated from North and most of Central America. Independently, a Russian geneticist, Alexander Serebrovsky, had proposed the concept of autocidal control using chromosome rearrangement for sterilization more than a decade earlier, but, because he antagonized Lysenko by rejecting Lamarckism, he ended up in scientific disfavor and died in a sanatorium in 1948. Brisola Marcondes et al. (14) point out that “This entomological case study emphasizes the danger of politics interfering with science, a still contemporary hot issue.”

Lysenko is long dead and for the most part forgotten; political interference with science, unfortunately, is still alive and well in many parts of the world. In this regard, the scientific enterprise in the United States has benefited enormously from the prescience of Abraham Lincoln, who, as the NAS website notes, in 1863 created the National Academy of Sciences, as “an independent honorary and consulting body with its own governance and structure” and with an “obligation to provide scientific and technical advice to any department of the Government” pro bono (15). Creating an independent consulting body distinct from the federal government was an important step in disentangling science policy from political power and has provided a model for other nations. The Lysenko affair is just one example of a pattern that recurs with depressing regularity, particularly in authoritarian regimes, according to which the scientific process, with its many safeguards (including replication and transparency), can be compromised by political expediency.