An international study published in the journal Nature has identified 1,260 genetic variants linked to personality, science communicator Jorge Alcalde said during an appearance on the radio programme La Tarde on the Spanish station COPE.
Alcalde said the macro-study analysed the DNA of more than 1,140,000 people of different sexes, social backgrounds, races and conditions. Of the 1,260 variants identified, 824 had never before been linked to personality, he said.
Genetics only partly explains personality
The research focused on the so-called Big Five traits, a framework long used in psychology to describe personality: openness to experience, extraversion, agreeableness, conscientiousness and neuroticism, or emotional instability. Alcalde said the study's central finding also challenges, in some respects, the idea that personality is largely inherited.
Alcalde said genetics does not weigh as heavily on personality as it might seem, although it remains a contributing factor. He explained that people carry a genetic predisposition that makes them more likely to be friendly, but that upbringing then determines how friendly a person actually becomes.
Alcalde said family environment, the behaviour children observe at home and, above all, a young person's social circle stand out as major influences in the study's analysis. He said a young person's friend group has even more influence on their personality than their own parents do. He concluded that personality results from a combination of genetics, which he put at around 4% to 5%, together with upbringing and the impact of friends.
Toxins as an 'invisible trap'
Alongside the genetics research, Alcalde discussed how environmental toxins can damage genetic health and cause serious illness over the long term, pointing to the health consequences of the September 11, 2001 attacks in New York, 25 years on.
Almost 3,000 people were killed directly in the attacks and more than 6,000 were injured in New York, Alcalde said. A further 9,000 people have since died as part of a health programme set up for those affected, with a high prevalence of respiratory diseases and cancers including prostate, lung, leukaemia and thyroid cancer. The health effects of exposure to Ground Zero dust have long been tracked by the World Trade Center Health Program, a federal initiative that monitors survivors, responders and residents exposed to the toxic cloud released when the towers fell.
Alcalde attributed the illnesses to the 1.2 million tonnes of pulverised material that filled the air after the collapse of the Twin Towers, which released highly carcinogenic and hazardous particles, including asbestos, lead, fibreglass, silica and polycyclic aromatic hydrocarbons. He said dry cement is dangerous on its own, but that when it combines with the humidity in the air, the body suffers an immediate chemical reaction in the lungs.
How toxins raise cancer risk
Alcalde explained how these substances end up causing cancers and blood disorders. He said many of the body's cells, when affected by the impact of these toxins over a long period and cumulatively, generate a stress reaction, an inflammatory reaction that can lead to a mutation, which carries a greater risk of cancer.
Alcalde also cited comments from Zohran Mamdani, the current mayor of New York City, who has said people fell ill because leaders they trusted lied to them. According to Alcalde, Mamdani said those leaders did not tell people the air was toxic, insisting instead that it was perfectly safe to breathe.
