The prevalence of the In(Lu) phenotype in the Japanese population was 0.02%, and we identified 13 known and 21 novel KLF1 alleles. The KLF1 mutations cause the reduced expression of the P1 antigen.

The Kidd blood group system consists of three common phenotypes: Jk(a+b−), Jk(a−b+) and Jk(a+b+), and one rare phenotype, Jk(a−b−). Jka/Jkb polymorphism is associated with c.838G>A (p.Asp280Asn) in exon 9 of the JK (SLC14A1) gene, and the corresponding alleles are named JK*01 and JK*02. The rare phenotype Jk(a−b−) was first found in a Filipina of Spanish and Chinese ancestry, and to date, several JK null alleles responsible for the Jk(a−b−) phenotype have been reported. We report seven novel JK null alleles, 4 with a JK*01 background and 3 with a JK*02 background, identified from Jk(a−b−) Japanese.

We established a human hybridoma cell line secreting monoclonal anti-Jk3 (HIRO-294). This antibody had unique specificity, recognising the Kidd glycoprotein including the Jk(a) /Jk(b) polymorphic site.

We identified three known and ten new silent KEL alleles from Japanese individuals with the K phenotype. The KEL allele with the c.299G>C (p.Cys100Ser) mutation was the most frequent.

The Dombrock blood group system consists of two antithetical antigens, Do(a) (DO1) and Do(b) (DO2), and seven high-prevalence antigens, Gy(a) (DO3), Hy (DO4), Jo(a) (DO5), DOYA (DO6), DOMR (DO7), DOLG (DO8) and DOLC (DO9). Do(a) /Do(b) polymorphism is associated with c.793A>G (p.Asn265Asp) in exon 2 of the DO (ART4) gene, and the corresponding alleles are named DO*01 and DO*02. The rare Donull or Gy(a-) phenotype lacks all Dombrock antigens, and the DO null alleles vary with both DO*01 and DO*02 backgrounds. We report a novel DO null allele, which has a c.268C>T (p.Gln90Stop) nonsense mutation with a DO*02 background identified from four unrelated Gy(a-) Japanese individuals.