Alpha-Globin Gene Analysis
Method Description Describes how the test is performed and provides a method-specific reference
This is a direct mutation analysis. Deletions within the alpha-globin locus and the Hemoglobin Constant Spring and alpha-thalassemia Saudi point mutations are identified by a multiplex ligation-dependent probe amplification assay. Fifteen probes that hybridize throughout the alpha-globin locus from the HS40 promoter region through the 3'HVR region are utilized in order to maximize the information needed to map the approximate location of nearly all DNA deletions that occur. In addition, a PCR-based assay is used to detect the presence of the alpha-3.7 and alpha-4.2 deletions.(Bunn HF, Forget BG: Hemoglobin: Molecular, Genetic and Clinical Aspects. Philadelphia, WB Saunders Company, 1986; Weatherall DJ, Higgs DR, Clegg JB, et al: Heterogeneity and origins of the alpha-thalassemias. Birth Defects: Original Article Series 1987;23:3-14; Schouten JP, McElgunn CJ, Waaijer R, et al: Relative quantification of 40 nucleic acid sequences by multiplex ligation-dependent probe amplification. Nucleic Acids Res 2002 Jun 15;30(12):e57)
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.
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.
Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result
Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Whole Blood: 2 weeks (if available) Extracted DNA: 3 months
Performing Laboratory Location The location of the laboratory that performs the test