Our Tests

PGD for HLA Matching

What is HLA Matching?

Allogeneic haematopoietic stem cell (HSC) transplantation represents the only curative option for leukemia and certain blood disorders, including β-thalassemia, sickle cell disease, Fanconi anemia, chronic granulomatous disease, Diamond-Blackfan anemia, Schwachman-Diamond syndrome, and Hyper IgM. The best possibilities of cure are provided by transplantation with Human Leukocyte Antigen (HLA)-identical sibling donors. Unfortunately, this ideal strategy cannot be used in the majority of cases because of the difficulty to find HLA-matched donors, even among family members.

If a pregnancy with a matched sibling is conceived, then the newborn umbilical cord blood can be collected during delivery and used to treat the affected sibling. Without intervention, there is a 25% chance of each sibling being a complete HLA match to their affected brother or sister. An increasing number of couples with a child affected by a hematological disease are requesting PGD for HLA matching to increase the chances of conceiving a healthy child who could become a future donor of umbilical cord blood stem cells to treat an affected recipient sibling.

What is PGD for HLA matching?

Preimplantation Genetic Diagnosis (PGD) for Human Leukocyte Antigen (HLA) matching is used to identify embryos that are HLA compatible with a child who is in need of a bone marrow or cord blood transplant. PGD for HLA can be performed in conjunction with testing for a single gene disorder if needed, in order to recommend embryos that are both HLA-matched to an affected sibling and free of the inherited condition.

How does RGI test for HLA?

The scientists at RGI were the first to develop a PGD strategy that is optimized for HLA matching. This procedure involves generating a DNA fingerprint of the affected child's HLA region, and then determining if the HLA region in an embryo is the same or different. PGD for HLA includes the analysis of at least eight polymorphic (unique) markers throughout the HLA complex, and has been helpful in detecting potential recombination (the normal crossing-over process by which genes are "shuffled" when being transmitted from one generation to the next) that may compromise the likelihood of a match. This approach also permits HLA testing of embryos to be combined with analysis of a known single gene disorder.