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The ghost twins

Updated: Mar 26


The ghost twins," also known as "hidden twins" or "non-manifested twins," are twins who are not visibly present at birth but exist in the DNA of the other twin.


femme enceinte apprend qu'elle a un bébé mort qui deviendra un jumeau fantôme

They result from a late division of the fertilized egg, which can occur up to four days after fertilization.

Ghost twins are generally very genetically similar to the other twin and may be of different sexes. They can be identified through genetic testing. However, they are not detected during pregnancy or at birth because they are not visible on ultrasounds or X-rays.


It is important to note that ghost twins are not independent living beings and cannot develop autonomously. Instead, they are genetic anomalies that may be present in the DNA of the other twin.


Ghost twins may be discovered during genetic testing for other reasons, such as paternity tests or DNA analyses for medical or scientific research. They can also be found when genetic abnormalities are detected in an individual, and the cause is being investigated.


It is essential to note that ghost twins are not common and represent a very small proportion of twins. Most twins are fraternal twins, meaning they developed from two independent fertilized eggs.


In summary, ghost twins are genetic anomalies that may be present in an individual's DNA, resulting from a late division of the fertilized egg. They are sometimes referred to as chimeras. They cannot be considered living, but their DNA, and sometimes more, persists in the body of the other twin. The only way to identify a ghost twin is through genetic testing.


What is chimerism?


Chimerism is a phenomenon that occurs when two or more genetically distinct individuals are present within the same organism.

This can happen in different ways, for example, when one fetus absorbs another during pregnancy, or when an individual receives an organ or tissue transplant from a different donor. Chimerism is also discussed in this blog.


cellule multicolore sur fond noir lors d'une analyse génétique

Chimerism can be partial or complete, depending on whether only certain organs or tissues are genetically different, or if the entire organism is composed of cells from multiple different individuals. Chimerism can be detected through genetic tests.


However, it is not always easy to diagnose, as chimeric individuals may not exhibit apparent symptoms.

Chimerism can have significant consequences for health, especially when it involves organs or tissues essential for the organism's functioning. It can also lead to difficulties in determining gender or paternity, as chimeric individuals may have different sex chromosomes in different cells of their bodies.


Chimerism can result from different biological processes, for example:


The absorption of one fetus by another during pregnancy, which can occur when two independently fertilized eggs develop together in the uterus. This condition is known as "superfetal chimerism" or "fetal chimerism."


Organ or tissue transplantation from a different donor, potentially resulting in the presence of foreign cells in the recipient's organism. This is known as "allogeneic chimerism" or "graft chimerism."


The absorption of fetal blood cells by the mother during pregnancy, which can lead to the presence of fetal cells in the mother's blood after childbirth. This condition is known as "materno-fetal chimerism" or "maternal chimerism."


Chimerism can be detected through genetic tests, which compare the DNA of different cells in the organism and determine if they originate from multiple different individuals. These tests can be used to diagnose chimerism and assess its effects on the individual's health."




What are the symptoms of chimerism?



Chimeric individuals may not exhibit apparent symptoms because chimerism can be partial, involving only certain cells or tissues of the organism. However, in some cases, chimerism can lead to symptoms and health complications.


Here are some examples of symptoms that may be associated with chimerism:

  • Genetic abnormalities: Chimerism can potentially result in genetic abnormalities in certain organs or tissues, leading to diseases or health disorders.

  • Pregnancy issues: Materno-fetal chimerism can cause pregnancy complications, such as miscarriages or premature births.

  • Reproductive problems: Chimerism may lead to reproductive issues, such as developmental abnormalities in reproductive organs or difficulties conceiving.

  • Health issues related to transplantation: Individuals who have received organ or tissue transplants may experience symptoms related to graft rejection, such as pain, fever, or health disorders.

It's important to note that chimerism can be challenging to diagnose, and symptoms may vary from individual to individual based on the severity and location of the condition.


How to know if I have a phantom twin?


It's not always easy to determine if you have a phantom twin, as these genetic anomalies are typically challenging to detect.


However, here are some ways that might help you find out if you have a phantom twin:

Undergo genetic tests: There are genetic tests that can help determine if you have a phantom twin. These tests can be performed on blood or saliva samples and involve comparing the DNA of different cells in your organism. If certain cells have DNA different from yours, it could potentially indicate the presence of a phantom twin.

Consult a geneticist: A geneticist is a healthcare professional who can assist in determining if you have a phantom twin. They can conduct genetic tests and help you understand the results.

Pay attention to genetic abnormalities: If you have unexplained genetic abnormalities that cannot be traced through your known genealogy, it could be a sign that you have a phantom twin. For example, if you have different sex chromosomes in different cells of your body, it might potentially indicate the presence of a phantom twin.



It's important to note that phantom twins are not common, and it's unlikely that you have one. If you have any questions or concerns about this, it's recommended to consult a doctor or a geneticist for advice and a health evaluation.

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