Eustachian Tube Growth and Development: Anatomy/Function. Protocol Description. This study measures Eustachian tube function and facial growth over time in three groups of children: one with recurrent ear infections, one with chronic middle ear fluid, and one with little past history of otitis media.
Causes of Kartagener syndrome. Kartagener syndrome is caused by a mutation in the DNAI1 gene, which makes a cellular protein required for normal functioning cilia (cilia line the respiratory tract) and sperm motility.
Nearly all cases of fragile X syndrome are caused by an alteration (mutation) in the FMR1 gene where a DNA segment, known as the CGG triplet repeat, is expanded. Normally, this DNA segment is repeated from 5 to about 40 times. In people with fragile X syndrome, however, the CGG segment is repeated more than 200 times.