DQ Alpha Genotyping uncovers important information for women who have experienced miscarriage and couples who have experienced one normal delivery and then recurrent miscarriages. In this blog post we explain the test and why it’s important.
Your Human Lymphocyte Antigen (HLA) system is part of what determines your unique immune system and what your immune system recognizes as foreign.
The DQ Alpha genotyping test is a specific kind of HLA (tissue) typing done at the DNA level. Class II HLA, found on the surface of white blood cells, include HLA-DR and HLA-DQ. Each tissue type is made up of an “A” or alpha part and a “B” or beta part. The B-cell is a type of white blood cell that manufactures antibodies. Researchers have discovered that mothers who are HLA-DQ alpha (DQA1) and/or DQ beta (DQB1) compatible with their fetuses tend to have a high rate of miscarriage before eight weeks of pregnancy.
Autoimmune Implications of HLA DQ alpha
Researchers have discovered that mothers who are HLA-DQ alpha (DQA1) and/or DQ beta (DQB1) compatible with their fetuses tend to have a high rate of miscarriage before eight weeks of pregnancy. Other studies show that mothers who are DQ alpha compatible with their fetuses can develop an exacerbation of autoimmune processes, such as rheumatoid arthritis and antiphospholipid antibody syndrome, during the early portions of their pregnancy.
Alloimmune Implications of HLA DQ alpha
Sometimes a couple wishing to have children will share certain determinants of the HLA system. If the couple shares a certain HLA DQ alpha determinant, the woman’s immune system natural killer (NK) cells that populate the uterine lining can start over-producing toxins called TH-1 cytokines. These activated NK (NKa+) cells attack the root cells of the embryo, the trophoblast, causing damage and compromising implantation of the embryo.
Basically, the couple has identical protein sequences on the surface of their cells. The woman’s body thinks the embryo is a growth that is part of her but shouldn’t be there, like a cancer, and so the natural killer cells destroy it.
There Are Possible Treatments for HLA DQ Alpha Matches
Some have a tendency to consider all couples who share the HLA DQ alpha determinant to be incapable of achieving a viable full term pregnancy. But others have found ways to treat the immune system. Once the association is discovered, more aggressive treatments can be tailored to a patient’s situation to prevent the autoimmune process from causing another miscarriage.
Another reason the test is important is because it can determine how IVF is conducted. NK cell activation only occurs after repeated exposures to DQa-“matching” embryos. This is why a couple with a DQa matching embryo can have a successful full term pregnancy. The DQa matching embryo reaches the uterus prior to NK cell activation. But, if untested and undiagnosed, repeated exposures to DQa “matching” embryos mean that uterine NK cells will become activated and can ultimately become permanent.
For more information about IVF and HLA-DQ alpha testing, you can read our colleague Dr. Scher’s blog here – http://haveababy.com/fertility-information/ivf-authority/dq-alpha-matching-in-ivf-controversy.
PDQ alpha genotyping is just one of the many tests we conduct at our lab. For more information about our tests or our reproductive immunology treatments, please contact us today. We’re specialists in reproductive immunology who provide consultations over the phone or in person with you and/or your physician. We provide lab testing for our patients as well as for other physician offices and for research studies.