Genetics Home > Diagnosis of Turner Syndrome
A diagnosis of Turner syndrome is confirmed with special blood tests. An early diagnosis of Turner syndrome is often made during prenatal testing because of an abnormal amniocentesis. For women with a mild form of Turner syndrome, diagnosis may occur later in life.
A doctor can suspect that a person has Turner syndrome based on the presence of certain features of the condition. A diagnosis of Turner syndrome is confirmed with special blood tests.
The point in life when Turner syndrome is diagnosed will depend on the severity of the condition. A diagnosis of Turner syndrome can be made during prenatal testing. Girls with several Turner syndrome features may be diagnosed during infancy or early childhood. For women with milder Turner syndrome, a diagnosis may occur later in life.
Any girl that is very short for her age or is growing at less than two inches per year should be checked for Turner syndrome.
A diagnosis of Turner syndrome is often made during prenatal testing because of an abnormal amniocentesis. Sometimes, certain Turner syndrome features, such as heart or kidney problems, may also be discovered during an ultrasound.
When the doctor suspects a person has Turner syndrome, he or she may order a special blood test, called a karyotype. This test looks at a person's chromosomes. The karyotype of X monosomy, which is the most common cause of Turner Syndrome, is termed "45X" -- meaning that an individual has 44 autosomes and a single X chromosome. The usual female karyotype is 46, XX.
The diagnosis of Turner syndrome caused by X chromosome defects may require specialized, molecular cytogenetic studies to identify small deletions or inversions of X chromosome material (see Turner Syndrome and X Chromosome Defects).
The genetic diagnosis of mosaic Turner syndrome may require the examination of many, many blood cells, and/or the examination of other cell types such as skin cells. The genotype of mosaic Turner syndrome is usually specified as 45X (10)/46XX (90) to indicate, for example, that 10 percent of cells examined were found to have X monosomy.