How to diagnose 47 XXX syndrome ?
How is 47 XXX syndrome diagnosed? 47 XXX syndrome may first be suspected based on the presence of certain developmental, behavioral or learning disabilities in an individual. The diagnosis can be confirmed with chromosomal analysis (karyotyping), which can be performed on a blood sample. This test would reveal the presence of an extra X chromosome in body cells. 47 XXX syndrome may also be identified before birth (prenatally), based on chromosomal analysis performed on a sample taken during an amniocentesis or chorionic villus sampling (CVS) procedure. However, in these cases, confirmation testing with a test called FISH is recommended in order to evaluate the fetus for mosaicism (when only a percentage of the cells have the extra X chromosome).