Mosaicizáció

Mosaicizáció is a biological phenomenon where an individual possesses two or more genetically distinct cell populations. These different cell lines originate from a single zygote, meaning the genetic variations arise after fertilization. This contrasts with chimerism, where an individual has cell populations from two or more distinct zygotes.

The most common cause of mosaicizáció is a mutation that occurs during early embryonic development, after the zygote has already begun to divide. If this mutation happens in a somatic cell, it will be present in all cells that descend from that mutated cell, but not in others. If the mutation occurs in a germ cell precursor, it can be passed on to offspring, leading to a phenomenon known as gonadal mosaicism.

Mosaicizáció can affect any tissue or organ in the body. The consequences depend on several factors, including the proportion of mutated cells, the type of mutation, and which tissues are affected. In some cases, mosaicizáció may have no observable effect. In others, it can lead to a range of conditions, from mild variations to severe genetic disorders. For example, certain forms of neurofibromatosis and achondroplasia can arise due to mosaicizáció.

Diagnosing mosaicizáció can be challenging. Standard genetic testing, which often analyzes cells from blood or saliva, might miss the mutation if it is present in a low proportion or confined to specific tissues. More specialized testing methods may be required to accurately identify and characterize mosaic genetic variations.