Identification of a DRB1*04:07-DRB4*01:03:01:02N haplotype in a native American individual.

The DRB4*01:03:01:02N null allele is predominantly associated with the HLA-DRB1*07-DQB1*03:03 haplotype. Several recent reports demonstrated a less frequent association of DRB4*01:03:01:02N with DRB1*04 carrying haplotypes in different populations. The ability to identify the presence of null alleles is extremely important in the setting of both solid organ transplants and hematopoietic cell transplants, and characterization of haplotypes carrying null alleles is crucial. In this paper, we report for the first time, an association of DRB4*01:03:01:02N null allele with a DRB1*04:07-DQB1*03:02 haplotype.