What is HLA Typing?
The human leukocyte antigen test (HLA) detects antigens (genetic markers) in white blood cells. The 4 types of human leukocyte antigens are: HLAA, HLAB, HLAC, and HLAD. The HLA test checks the tissue compatability and recipient / donor tissue typing. It is also used in genetic counseling and paternity testing. (Research only.
Human Leukocyte Antigen (HLA) Typing is done by taking a sample of blood or cheek cells and analyzing it in a laboratory. The typing process has two steps. The first is called serological typing, which is a broad definition of your bone marrow type. The second, more specific typing is done using a DNA method. Your bone marrow “type” is designated by a series of 10 alpha-numeric combinations. There are millions of possible combinations. Your HLA type is inherited from your parents: one half from your mother and one half from your father. Just as you and your siblings may have inherited similar features, such as hair or eye color, you may also have inherited the same HLA type. The likelihood of finding an HLA match with a family member is approximately 25-30%. HLA markers are found on the white blood cells (leukocytes) of a patient. A donor’s markers are compared to the patient’s markers to determine the potential for a match.
