“The Legacy of the Genes”, in which both title and subtitle (“What Science Can Teach Us About Aging”), is a self-help book, not a science book. Self-help in a good way: recommendations based on scientific knowledge, as much as possible, without the barrier of technical language.
The booklet by Mayana Zatz and Martha San Juan França does not spare references to research by renowned institutions. The project 80mais is highlighted, a study in progress since 2010 at the Center for the Study of the Human Genome and Stem Cells (CEGH-CEL), at USP, created by Zatz.
The geneticist gained notoriety in 2008 by successfully defending, in the Supreme Court, research with stem cells derived from human embryos. Today, pluripotent cells can be obtained without destroying embryos and are among the many tools Zatz and colleagues use to investigate biological secrets of aging.
It is the theme of 80mais, centered on genome sequencing (DNA spelling) of healthy and active individuals over 80 years of age. By sifting through the genes of luminaries like physicist José Goldemberg, now 93 years old, the project aims to identify genetic variants that might explain why some old people remain in good physical and mental health despite the inevitable physiological decay.
As narrated in the book by science journalist Martha San Juan França, the 80plus has grown a lot over the years. Three partnerships contributed to this.
First, Zatz’s team was approached by the Sabe project, from the School of Public Health at USP, which gathered clinical data from people over 60 years old since the year 2000. Later, the Albert Einstein Hospital proposed adding magnetic resonance images to the collection at the University. brain of the participants.
The American company Human Longevity, owned by the notorious scientist and entrepreneur Craig Venter, was willing to sequence the complete genomes of hundreds of elderly Brazilians for free — as long as they had access to the data. Afterwards, foreigners became disinterested, but the amount of information enriched the bank of the CEGH-CEL.
With such an arsenal, one could conclude that a lot has been discovered about which genes influence longevity and well-being in old age. But not: still little is known about it, which perhaps explains the brevity of the work (compare with the 680 pages of a bestseller like “The Gene”, by Siddartha Mukherjee).
Although the book explains well that old age is not a disease, genomics faces the same difficulties in elucidating the ailments of the elderly found to fulfill the promise of unveiling illnesses and inaugurating the promised personalized precision medicine.
Two decades after the publication of the human genome, there are examples of successful treatments thus derived, but few. Genes are known to be correlated with certain conditions —from breast cancer to Alzheimer’s—, but such knowledge has hardly been able to defeat tumors, dementia or depression.
It is true that the volume by Zatz and França carefully explains the limits of this scientific strategy of shooting at what can be seen (billions of genetic letters in DNA) in the hope of hitting what is not yet seen (biochemical minutiae of diseases that give clues to develop therapies and drugs).
In one or another passage, the text still uses reductionist expressions, for example, when stating that a gene “determines” such a characteristic or protein. But the book sails leagues away from the rhetorical hyperbole that helped raise the nearly $3 billion Human Genome Project.
By presenting demographic characteristics of aging in Brazil, “O Legado dos Genes” makes it clear that the genome, after all, has little to do with the depressing situation of the elderly here. The Sabe project, for example, found that almost everything got worse between the 2000 and 2015-2017 survey.
The reported incidence of hypertension was from 53.3% to 66.3%; diabetes, from 17.9% to 28.3%; cancer, from 3.3% to 9.3%; heart problems, from 20% to 23.8%. Only chronic lung diseases declined, from 12.2% to 7.9%.
Given the meager results of genomic research to mitigate the ills of old age and the living conditions that we relegate elderly people to in Brazil, the work offers little to those who enter the dark tunnel of 60 years. No more than common sense: remain intellectually active, even retired, exercise, take care of food and sleep, preserve optimism, strengthen ties with friends and family…
With the Covid-19 pandemic, of course, all this got complicated, and the lives of the elderly only got worse. Several breadwinners died, many still active lost jobs, survivors were confined and depressed.
França portrays some old men who have survived a great deal, including nonagenarians and centenarians who defeated the new coronavirus. Those who have not yet arrived there (and are afraid of not getting there) would leave reading less overwhelmed if these resisters gained more life and space in the book, as never before have the grandparents, parents and children of this battered country needed so much stories to overcome them.