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Test Code ATHAL Alpha Thalassemia DNA Screen

Important Note

This assay detects six of the most common deletions in HBA1 and HBA2 found in patients with alpha-thalassemia.

Clinical System Name

Alpha Thalassemia DNA Screen


α Thalassemia



Alpha Globin

Sample Requirements

Specimen: Whole Blood

Container(s): Lavender/EDTA

Preferred Vol: 2.0 mL

Minimum Vol: 1.0 mL


Specimen: DNA

Container(s): Sterile plastic tube

Preferred Vol: 20-30 ul of 100ng/ul concentration



Note: Yellow top ACD tubes also acceptable. Buccal cells are acceptable for transplant patients. For other specimen types contact the UW Genetics Lab (598-6429).

Processing Instructions

Reject due to: Heparinized sample or Formalin-fixed paraffin-embedded tissues

Spin: N


Temp: RT

Storage location: Do not spin or separate specimen. Store whole blood affixed with a large computer label in the CPA refrigerator send outs rack.


Off-site collection: Do not spin or separate specimen. Transport at room temperature.


Specimen Type Temperature Time
Whole blood Room temp 1 w
  Refrigerated 1 w



STAT Performed TAT
N Collected daily, performed weekly at UW 1 -2 w


Performing Laboratory

University of Washington

Dept of Laboratory Medicine

Genetics Lab

1959 NE Pacific St, NW220
Seattle, WA 98195


Phone Number: (206) 520-4600



Department:  Send Outs

Phone Number: (206) 987-2563



Reference Range

Interpretive report provided.





Method: This assay detects six of the most common deletions found in patients with alpha-thalassemia [Chong et al, 2001]. In two of these common deletions, the 3.7 kb deletion type and the 4.2 kb deletion type, only one of the four alpha globin genes is deleted. In the other four common deletions, known as the SEA (Southeast Asian) deletion type, FIL (Filipino) deletion type, the THAI (Thailand) deletion type, and the MED (Mediterranean) deletion type, two adjacent (cis) alpha-globin genes are deleted (both from the same chromosome). About 95% of all alpha-thalassemia is due to gene deletions that are detected by this test (detection rates may vary in specific populations).

Analytical Volume: 1.0 mL whole blood


CPT Codes

81257 (updated 8/17/17 by sstasi)

Send Out Instructions


Reference Test Name: Alpha Thalassemia DNA Screen
Reference Test Number: ATHAL
Instructions: Send out M - F with the UW courier.