The Kidd minus-minus phenotype in a Caucasian

Area of Science:

• * Hematology
• * Immunology
• * Genetics

Background:

• * The Kidd blood group system (JK) is clinically significant for transfusion medicine.
• * The Jk(a-b-) phenotype is extremely rare, posing challenges in finding compatible blood.
• * Understanding blood group genetics is crucial for preventing transfusion reactions.

Observation:

• * A Caucasian individual presented with the rare Jk(a-b-) blood type.
• * A single-specificity antibody with strong reactivity was detected.
• * The antibody was fully absorbed by both Jk(a+b-) and Jk(a-b+) cells.

Findings:

• * No compatible blood donors were identified for the patient.
• * Autotransfusion was performed due to the lack of compatible donors.
• * Family studies did not identify other individuals with the Jk(a-b-) phenotype.

Implications:

• * The case raises questions about the existence of a third allele at the Kidd locus.
• * Further research is needed to elucidate the genetic basis of this rare phenotype.
• * This case highlights the importance of comprehensive blood group genotyping for transfusion safety.