In 1902’s Just So Stories, Rudyard Kipling famously explained how the leopard got his spots in what would today be deemed an…
I haven’t thought or written much about human genetics since COVID hit, instead cranking out articles about the novel coronavirus and the repercussions as it evolves and spreads.
Now it’s time to revise my human genetics textbook. The thirteenth edition of Human Genetics: Concepts and Applications came out in September 2020. I’d signed off on the final page proofs that April, back when New York City was the COVID epicenter for the US. I only had time to swap in a SARS-CoV-2 photo for one of Zika virus, and replace a flu paragraph with what we knew about COVID at that time.
With each revision, I think back on how the field has changed in the 20 years since the first edition. That typically means updating coverage of genetic tests and technologies – topics like cell division, Mendel’s laws, DNA and RNA and protein, evolution and populations – remain the same. This time though, in the face of vaccine hesitancy, the importance of understanding basic genetics is much more compelling. The context: the vaccines work by taking advantage of the way that genes control protein production.
Those who think the COVID vaccines are made of fetal parts, will scar grandchildren, or make a person magnetic are fortunately in an ever-shrinking minority. But their reticence is countering the building of herd immunity, creating pockets of vulnerability that may beckon and nurture viral variants that spread more readily. They are delaying the conquering of the virus.
Fear of the unknown is powerful, and unfortunately one needs a bit of familiarity with the chemistry and biology behind the vaccines to understand how they work, and to appreciate how safe they are. Many people have gotten up to speed on the science from the excellent media coverage of the pandemic. But writing my textbook has given me a different window onto what the public knows, revealing a relationship to age.
My book began in 1993 as a college textbook, with a few high school AP classes adopting it. Now, though, McGraw-Hill is marketing it to grades 9 to 11. That’s consistent with state science standards that require even 7th graders to know that DNA encodes mRNA, which encodes protein. Understanding that relationship – called the “central dogma of molecular biology” – makes it clear exactly how a DNA or RNA-based vaccine instructs our cells to make and release spike proteins just like the ones that festoon the viruses. The spikes then stimulate a multi-pronged immune response, limiting infection to perhaps a few fleeting viruses in the nose and throat, and not even that once most of us are vaccinated.
I’ve given zoom lectures on the COVID vaccines to middle school students, and was happy to realize that they already knew, in detail, how they work. Science teachers have done a great job! Then the kids inform their parents and others. Perhaps understanding the science behind vaccines can help to counter the emotional responses of fear and distrust.
An unexpected benefit of the pandemic may be the quelling and countering of science phobia. I never thought I’d see the day when regular people, non-nerds like me, would be talking about messenger RNA! SARS-CoV-2 has brought unprecedented suffering, but it might also have raised the level of science literacy – and inspired a new generation of scientists.