Which genetic tests are recommended for confirming a diagnosis of Turner Syndrome in suspected cases?

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 ¹. 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 and 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.