Diagnosis and Testing
Is there more than one type of test for Trisomy 13?
There are a few types of genetic tests that can diagnose Trisomy 13. Trisomy 13 can be diagnosed through fluorescence in situ hybridization (FISH) testing, karyotype, or chromosomal microarray. The basic test is called a karyotype, where the chromosomes are counted and examined in a laboratory called a cytogenetic lab. This test takes about 7-10 days for a result. A rapid, preliminary test for trisomy 13 is called fluorescence in situ hybridization or FISH. This test uses a brightly colored probe to quickly count the number of copies of a given chromosome and can provide an early result in 2-3 days. A newer way to examine genetic material is called a chromosome microarray, which looks for extra or missing pieces of genetic material. This test can also be used to diagnose trisomy 13. Your healthcare provider may order one type of test or another based on turnaround time, the capability of their genetics laboratory and how strong his/her suspicion is for trisomy 13.
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