Which of the following is true about Jk(a-b-) phenotype?

The Jk(a-b-) phenotype refers to an uncommon expression of the Kidd blood group system, specifically indicating that neither the JkA nor the JkB antigens are present on the red blood cells. Among the various Kidd blood phenotypes, Jk(a-b-) is indeed one of the rarest, with its prevalence differing across ethnic groups.

This rarity stems from genetic inheritance patterns where individuals must inherit specific alleles that lead to the absence of both antigens. Understanding the population distribution of blood types is key in transfusion medicine, and recognizing that Jk(a-b-) is less frequent highlights its importance, especially when considering donor-recipient compatibility in transfusions.

In contrast, the other options do not accurately describe the Jk(a-b-) phenotype. While transfusion reactions can be influenced by the presence of certain antibodies, the connection of Jk(a-b-) with fewer reactions is not definitively established. Furthermore, stating that it is commonly found contradicts the known statistics regarding its prevalence, and claiming that it can donate to any Kidd phenotype overlooks the fact that the presence of antigens is critical in determining compatibility for transfusion.