A group of scientists at Columbia National University documented a case of twins from different parents during a study of tests requested by a man who asked about the paternity of children.
The case began in August 2018, when the Genetics and Population Identification Group of Columbia National University (UNAL) received a request to establish the paternity of two male twins with genetic markers, from the alleged father, who was suspected of their kinship with children and the necessary proof.
According to a statement from the National University’s news agency, after comparing the DNA of the alleged father of a pair of twins, the Group “showed that this coincided with the genetic profile of one of them, meaning that for the other it was an exclusion. from paternity “.
Scientifically, the case is known as heteropaternal superfertilization, a rare phenomenon that occurs when a second egg, released during the same menstrual cycle, is fertilized by a sperm from a different man in a separate sex.
The doctor of Science-Biology National University, Lilián Andrea Casas Vargas, said that when there are very difficult cases or if you want to be sure of the result of paternity tests, the laboratory performs other markers.
In this case, he added, one known as the “Y chromosome panel” was made, taking into account that the twins are men, Casas explained.
Procedure
The scientists explained that this procedure is a widely used tool in parental testing. “The Y chromosome is secreted only by the paternal line and does it as a whole from one generation to the next, it never changes.”
“So, by not changing, it is expected that those markers of the Y chromosomes will be completely identical to those of the father. In this case, the genetic profile that coincides with one of the twins is observed again, while 14 out of 17 have been identified with others. without coincidences, which corroborated the exclusion “, adds the information.
Casas pointed out that according to the protocols established in the laboratory, when a case of paternity arrives and results in “exclusion”, the whole process is repeated to confirm that there were no technical errors during the analysis.
This is how they called again those involved who had other samples taken, and the results were the same, so the case was confirmed, whose report was published in the Biomedical Journal of the National Institute of State Health.
11,000 tests a year in Colombia
William Usaquén, the group’s director, was quoted in the publication as saying that an average of 11,000 paternity tests are performed in the country each year.
“Although it is a simple procedure, this (test) has a very high emotional load due to the type of social and cultural implications it has. The opinions of the parentage reveal a series of prejudices still latent in Colombian society regarding issues such as motherhood or sexuality, for example, “said Usaquén.