GRK3 and infection: In WHIM (warts, hypogammaglobulinemia, infections, and myelokathexis) syndrome, heterozygous mutations in the C‐terminus of CXCR4 result in a similar truncation to the one we describe here, which ablates the binding of GRK3 and GRK6, leading to defective CXCR4 phosphorylation and internalization and enhanced chemotactic responses to ligand.39