Description of a new HLA-E (E*01031) allele and its frequency in the Spanish population

An HLA-E polymorphism study by oligotyping and DNA sequencing was carried out in the Spanish population. As a result, a new HLA-E allele (E*01031) initially assigned by polymerase chain reaction oligotyping as E*0104 was found. This allele presents a synonymous change at codon 77 (AAT-->AAC; Asn) when compared with the E*01032 allele. This position is located in the alpha-helix (alpha 1-domain) and is involved in the peptide binding region of the hypothetical HLA-E molecule. Among 60 Spanish individuals, HLA-E*0101 presents the highest phenotype frequency, followed in decreasing order by E*01032, E*01031 (new allele), and E*0102. Also, new partial intron 1 and complete intron 2 sequences from E*0101, E*01031, and E*01032 are described; the sequences are identical among the three forms. However, the intron 2 sequence of the E*0102 allele bears a two-base deletion not found in apes.