Somatic mosaics have been created in Drosophila using X‑ray treatment and the use of irradiation to induce somatic mutation has been a useful technique in the study of genetics.True mosaicism should not be mistaken for the phenomenon of X-inactivation, where all cells in an organism have the same genotype, but a different copy of the X chromosome is expressed in different cells. The latter is the case in normal (XX) female mammals, although it is not always visible from the phenotype (as it is in calico cats). However, all multicellular organisms are likely to be somatic mosaics to some extent. Gonosomal mosaicism
Gonosomal mosaicism is a type of somatic mosaicism that occurs very early in the organisms development and thus is present within both germline and somatic cells. Somatic mosaicism is not generally inheritable as it does not usually affect germ cells. In the instance of gonosomal mosaicism, organisms have the potential to pass the genetic alteration, including to potential offspring because the altered allele is present in both somatic and germline cells. Brain cell mosaicism
A frequent type of neuronal genomic mosaicism is copy number variation. Possible sources of such variation were suggested to be incorrect repair of DNA damages and somatic recombination. Mitotic recombination
One basic mechanism that can produce mosaic tissue is mitotic recombination or somatic crossover. It was first discovered by Curt Stern in Drosophila in 1936. The amount of tissue that is mosaic depends on where in the tree of cell division the exchange takes place.
Those that undergo a carpal tunnel release are nearly twice as likely as those not having surgery to develop trigger thumb in the months following the procedure.While outcomes are generally good, certain factors can contribute to poorer results that have little to do with nerves, anatomy, or surgery type. One study showed that mental status parameters or alcohol use yields much poorer overall results of treatment.Recurrence of carpal tunnel syndrome after successful surgery is rare. History
The condition known as carpal tunnel syndrome had major appearances throughout the years but it was most commonly heard of in the years following World War II. Individuals who had had this condition have been depicted in surgical literature for the mid-19th century. In 1854, Sir James Paget was the first to report median nerve compression at the wrist in two cases.The first to notice the association between the carpal ligament pathology and median nerve compression appear to have been Pierre Marie and Charles Foix in 1913. They described the results of a postmortem of an 80-year-old man with bilateral carpal tunnel syndrome. They suggested that division of the carpal ligament would be curative in such cases. Putman had previously described a series of 37 patients and suggested a vasomotor origin. The association between the thenar muscle atrophy and compression was noted in 1914. The name "carpal tunnel syndrome" appears to have been coined by Moersch in 1938.In the early 20th century there were various cases of median nerve compression underneath the transverse carpal ligament.