Colombian woman discovers that twins have different fathers in rare case of superfertilization

A woman on Colômbia went to a laboratory for paternity testing of her twins. The result showed that the boys had different biological fathers. The case, analyzed by Universidade Nacional of Colômbia, was released this April.

Cientistas repeated the tests to confirm the diagnosis. Trata is heteroparental superfertilization, when two eggs from the same menstrual cycle are fertilized by sperm from different men. The phenomenon is considered extremely rare.

Routine Exame led to discovery

The mother sought the laboratory two years after the birth of the twins. The objective was to confirm the paternity of one of the supposed fathers. Genetic analysis, however, indicated incompatibility in one of the boys.

Pesquisadores of Laboratório of Genética of Populações and Identificação repeated the entire procedure. The result remained identical. Apenas, one of the twins was genetically compatible with the man tested. The other had a completely different profile.

Understand the case: Colombian woman pregnant with two different men has twins with different biological parents in rare case

Técnica of microsatellite markers confirmed the case

The scientists used analysis of 17 microsatellite markers, stretches of DNA that function as genetic fingerprints. Amostras of blood from the mother, the twins and the supposed father were collected.

In the laboratory, DNA was isolated, amplified and labeled with fluorescent substances. Equipamentos identified the genetic patterns. The results showed full compatibility in one twin and exclusion in the other.

• Coleta of blood samples from mother and children
• Isolamento and DNA amplification
• Análise of 17 microsatellite markers
• Comparação with alleged father’s material
• Repetição completes the validation exam

Diretor from the laboratory reports surprise

William Usaquén, director of the laboratory for 26 years, stated that this was the first case witnessed by the team. Geneticist Andrea Casas, who participated in the analysis, said that the theoretical possibility was known, but had never been confirmed in direct contact.

Follow: all about Colômbia DNA

The researchers highlighted that paternity tests follow strict privacy protocols. Nenhum details of the mother’s personal life were investigated beyond what was necessary for genetic analysis.

Fatores that make the phenomenon rare

Para If heteroparental superfertilization occurs, the woman needs to release more than one egg in the same menstrual cycle. Além Furthermore, it is necessary to have relationships with different partners within the fertile window.

Eggs remain viable for 24 to 48 hours. Espermas can survive up to 72 hours in the female body. Essa combination of simultaneous events is considered unlikely.

Muitos cases may go unnoticed, as paternity tests are not routine. The estimate is one case for every 13,000 births, although the number may be higher with advances in genetic testing.

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Médicos explain the biological mechanism

Obstetrician Daniela Maeyama of Maternidade São Luiz Star explained that releasing multiple eggs in the same cycle is possible, although uncommon. Cada egg can be fertilized by sperm from a different partner if intercourse occurs during the fertile window.

Especialistas remember that fraternal twins result from different eggs. In the case of different parents, the babies are genetically half-siblings. The phenomenon occurs in humans, but with very low frequency in scientific literature.

Avanços in genetics reveal previously unknown situations

The Colombian episode illustrates how modern DNA techniques make it possible to identify rare biological events. Similar Casos have been reported in other countries, but always in small numbers.

Cientistas reinforce that the discovery does not change the family bond. The focus remains on technical analysis. The study was published and analyzed by Universidade Nacional and Colômbia teams.