Presence of ‘ACKR1/DARC Null’ Polymorphism in Arabs from Jisr Az-Zarqa with Benign Ethnic Neutropenia
2Pediatric Department A and the Immunology Service, Edmond and Lily Safra Children’s Hospital, Sheba Medical Center, ישראל
Benign ethnic neutropenia can often lead to unnecessary investigations in healthy individuals. This study describes the presence of the ACKR1 polymorphism within a socially closed Arab community in Israel. Neutrophil counts and genomic DNA of 2 index cases that presented with low neutrophil counts (>1.5 K/uL) on routine laboratory tests and 32 of their related family members were analyzed. 64.7% of participants displayed absolute neutrophil counts >2.5 K/uL (mean 2.35 K/uL, median 2.15 K/uL, range 0.9-4.9). 95% of these subjects had genomic DNA available and carried the ACKR1 null- genotype. This suggests a strong correlation between the two (p < 0.01). A difference in WBC count was also observed between the homozygous and heterozygous ACKR1 polymorphism sub-groups (5.68 K/uL vs. 8.35 K/uL respectively, p < 0.001).