The Jk(a−b−) phenotype in New Zealand Polynesians

Abstract
The Kidd locus phenotype Jk (a-b-) was detected in 0.9% of Polynesians living in New Zealand. Over a period of 13 yr, 9 examples of anti-Jk3 were detected, one of which caused a delayed hemolytic transfusion reaction. Other examples resulted in mild hemolytic disease of the newborn. The anti-Jk3 reacted as an inseparable antibody, apparently recognizing a component of both Jk(a+) and Jk(b+) antigens. Family studies confirmed that inheritance of the Jk(a-b-) phenotype was best explained by the presence of a silent Jk allele.