21-Hydroxylase Gene (CYP21A2), Full Gene Analysis, Prenatal
Method Description Describes how the test is performed and provides a method-specific reference
Four sets of primer pairs amplify all possible recombinant forms of CYP21A2, CYP21A1P (the pseudogene), and their hybrids 5'-CYP21A2/CYP21A1P-3' and 5'-CYP21A1P/CYP21A2-3' via PCR to determine whether there are large rearrangements between the gene and pseudogene. Fluorescent DNA sequence analysis is then performed on all exons of the active form of CYP21A2 and any presumed active hybrid to test for the presence of sequencing mutations (GenBank accession number: NM_000500.5). If necessary, further analysis may be performed on nonexpressed copies of CYP21A2 or hybrids to gain insight into possible rearrangements. In addition, multiplex ligation-dependent probe amplification (MLPA) is performed to determine exact copy numbers of the active gene (CYP21A2), its inactive pseudogene (CYP21A1P), and any rearrangements. However, this technology cannot determine the cis/trans status (cis=same chromosome, trans=opposite chromosomes) of the identified gene, rearrangement, or mutation. Family studies of blood relatives might assist in determination of the cis/trans status.(Cradic KW, Grebe SK: A Diagnostic Sequencing Assay for CYP21 Based on Promoter Activity Provides Better Understanding of Gene Rearrangements. Abstract. Endocrine Society Annual Meeting, ENDO 2005)
PDF Report Indicates whether the report includes an additional document with charts, images or other enriched information
Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.
Monday; 8 a.m.
Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.
Varies; DNA: 12 days; Amniotic fluid/chorionic villi (confluent culture): 15 days
Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result
Varies; DNA: 21 days; Amniotic fluid/chorionic villi: 30 days
Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
DNA: indefinitely; patient must opt out; Amniotic fluid/chorionic villi: until testing is completed
Performing Laboratory Location The location of the laboratory that performs the test