AP BIOLOGY

Detailed explanation-1: -The Kidd blood group system, discovered in 1951, consists of three known antigens, designated Jka, Jkb, and Jk3, all of which are encoded by a gene known as SLC14A1 (solute carrier family 14, member 1). The Jka antigen occurs in more than 90 percent of blacks, 75 percent of whites, and 70 percent of Asians.

Detailed explanation-2: -Anti Jka antibody was identified in eluate obtained from neonatal red cells by heat elution method. On red cell phenotyping, mother was found to be Jka antigen negative; father and neonate were found to be Jka antigen positive. Antibody was observed to be of IgG type on Dithiothreitol (DTT) treatment.

Detailed explanation-3: -In this terminology, a six-digit number is adopted for each authenticated antigen belonging to a blood group system where the first three numbers represent the system and the last three numbers represent the antigenic specificity.

Detailed explanation-4: -The primary system Kidd antigens (Jka and Jkb) play a key role in urea transport through the membrane of red blood cells (RBC) [1]. They are present in Kidd proteins, which are codified by codominant alleles of a gene expressed in erythrocytes, endothelial cells and other tissues.