Genetic testing to confirm a diagnosis of Turner syndrome in suspected cases primarily involves karyotype analysis of peripheral blood lymphocytes to identify the characteristic monosomy X (45,X) or other chromosomal abnormalities such as mosaicism or structural X chromosome anomalies. This standard cytogenetic test remains the first-line diagnostic tool recommended in UK clinical practice guidelines NICE NG137. In addition, fluorescence in situ hybridisation (FISH) or chromosomal microarray analysis (CMA) may be employed to detect low-level mosaicism or structural abnormalities not easily identified by conventional karyotyping, enhancing diagnostic sensitivity. These methods are supported by recent literature emphasizing their utility in complex or ambiguous cases Redel & Backeljauw 2018.
Therefore, the diagnostic approach integrates conventional karyotyping as the cornerstone, supplemented by FISH or CMA when necessary to confirm Turner syndrome in suspected patients.
Key References
- NG137 - Twin and triplet pregnancy
- NG241 - Ovarian cancer: identifying and managing familial and genetic risk
- CG164 - Familial breast cancer: classification, care and managing breast cancer and related risks in people with a family history of breast cancer
- CG156 - Fertility problems: assessment and treatment
- (Redel and Backeljauw, 2018): Turner Syndrome: Diagnostic and Management Considerations for Perinatal Clinicians.