Introduction Homozygous deficiencies of complement C4A or C4B are detected in 1–10% of populations. In genome-wide association studies C4 deficiencies are missed because the genetic variation of C4 is
IntroductionHomozygous deficiencies of complement C4A or C4B are detected in 1–10% of populations. In genome-wide association studies C4 deficiencies are missed because the genetic variation of C4 is