Learn About Mosaicism
Mosaicism is a condition in which cells within the same person have a different genetic makeup. This condition can affect any type of cell, including:
- Blood cells
- Egg and sperm cells
- Skin cells
Chromosomal mosaicism; Gonadal mosaicism
Mosaicism is caused by an error in cell division very early in the development of the unborn baby. Examples of mosaicism include:
- Mosaic Down syndrome
- Mosaic Klinefelter syndrome
- Mosaic Turner syndrome
- Mosaic neurofibromatosis
Symptoms vary and are very difficult to predict. Symptoms may not be as severe if you have both normal and variant cells.
Treatment will depend on the type and severity of the disorder. You may need less intense treatment if only some of the cells are variant.
James Grifo is a Reproductive Medicine provider in New York, New York. Dr. Grifo is rated as an Elite provider by MediFind in the treatment of Mosaicism. His top areas of expertise are Mosaicism, Infertility, and Ovarian Hyperstimulation Syndrome.
Stephen Chanock is a Pediatrics provider in Potomac, Maryland. Dr. Chanock is rated as an Elite provider by MediFind in the treatment of Mosaicism. His top areas of expertise are Mosaicism, Menopause, Gliomatosis Cerebri, Esophageal Cancer, and Hormone Replacement Therapy (HRT).
Svetlana Vorsanova practices in Moscow, Russian Federation. Ms. Vorsanova is rated as an Elite expert by MediFind in the treatment of Mosaicism. Her top areas of expertise are Mosaicism, Ataxia-Telangiectasia, Autism Spectrum Disorder, and Turner Syndrome.
How well you do depends on which organs and tissues are affected (for example, the brain or heart). It is difficult to predict the effects of having two different cell lines in one person.
In general, people with a high number of variant cells have the same outlook as people with the typical form of the disease (those who have all variant cells). The typical form is also called non-mosaic.
People with a low number of variant cells may be only mildly affected. They may not discover that they have mosaicism until they give birth to a child who has the non-mosaic form of the disease. Sometimes a child born with the non-mosaic form will not survive, but a child born with mosaicism will.
Complications depend on how many cells are affected by the genetic change.
A diagnosis of mosaicism may cause confusion and uncertainty. A genetic counselor may help answer any questions about diagnosis and testing.
There is currently no known way to prevent mosaicism.
Summary: The purpose of this research study is to learn more about variants in the TP53 gene both associated with Li-Fraumeni Syndrome (LFS), a hereditary cancer risk condition, and TP53 variants found in the blood for other reasons (e.g. ACE/CHIP and mosaicism).
Summary: Somatic mosaicism in cancer associated genes is one potential explanation for discordance in childhood cancer that has not been fully explored to date. This pilot study will focus on twins with central nervous system (CNS) tumors who are identified through the Children's Oncology Group's Project: EveryChild (PEC) registry or volunteer.
Published Date: November 06, 2024
Published By: Anna C. Edens Hurst, MD, MS, Associate Professor in Medical Genetics, The University of Alabama at Birmingham, Birmingham, AL. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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Jelin AC, Van den Veyver IB. Preconception and prenatal screening and diagnosis. In: Cohn RD, Scherer SW, Hamosh A, eds. Thompson and Thompson Genetics and Genomics in Medicine. 9th ed. Philadelphia, PA: Elsevier; 2024:chap 18.