For decades in the Cândido Godói (CG) municipality in Brazil, there was a strange mystery: The rate of twin births is significantly higher than the surrounding area, and twin births around the world.
Studies have put the twin birth rate at 10 percent in one district, which is “significantly higher than the 1.8 percent rate for the state of Rio Grande do Sul as a whole”. While intriguing, people have concocted strange explanations for why so many twins are born in the area, from something in the water to strange minerals.
A book by journalist Jorge Camarasa went stranger, proposing that the phenomenon was the result of experiments conducted by Nazi physician Josef Mengele, sometimes referred to as the “Angel of Death” for his terrible crimes and experiments as chief doctor at Auschwitz.
During his time at Auschwitz, Mengele experimented on twins, helping to fuel this (almost certainly untrue) theory.
“Mengele ordered his staff to measure and record every aspect of the twins’ bodies. He drew large amounts of blood from the twins and sometimes performed other painful procedures on them,” the United States Holocaust Memorial Museum explains of Mengele. “Mengele also murdered sets of twins at the same time in order to conduct autopsies of their corpses.”
As the war was ending, Mengele fled Auschwitz and disguised himself as a German officer, before surrendering to the US. He was released before the US realized he was a wanted war criminal, and returned to Germany for a few years, before fleeing to Argentina fearing arrest, and then Paraguay, and finally, Brazil where he died of a stroke in 1979.
“According to Camarasa, Mengele could have lived and worked as a physician in CG in the beginning of the 1960s, after living in Buenos Aires,” where he continued unspecified experiments on twins, a study looking into the cause of the twin phenomenon explains.
This study assessed the claim by looking at twin rates before, during, and after Mengele had stayed there according to Camasara, “even though Camarasa’s suppositions were not based on any actual historical records available”.
Looking at baptism records, the study did find that twins were born at a higher rate in the area from 1959 to 2008. However, the researchers found that there was “no increase on the twinning rate in CG between the period 1964–1968 and the remaining years”, during or after Mengele was supposedly there.
Instead, the team put the cause down to the genetic “founder effect”, where a new colony is established by a small number of people.
“The colonization history of CG is suggestive that a genetic founder effect may have played a role in this process, leading to high shifts in allele frequency between the ancestral and the derived population. Because it is a random process, founder effects have unpredictable phenotypic effects, which, in this specific case, may be a high frequency of twinning,” the team wrote in their discussion, adding “strong evidence for the hypothesis of a genetic founder effect comes from the higher inbreeding coefficient found for women who gave birth to twins compared to other women”.
The team hoped that the study would provide relief for people living in Cândido Godói, as they ruled out the possibility that their twin births were the result of Nazi experiments.
“In this sense, our study illustrates how knowledge of population history and the genetic consequences may be of direct interest for the populations under study”, they added.
The study is published in PLOS ONE.
Source Link: The Cândido Godói Twin Phenomenon: Why Are So Many Twins Born Here?