The Fc gammaRIIIA-158F allele is a risk factor for systemic lupus erythematosus.
OBJECTIVE
To study whether the Fc gammaRIIIA-158V/F polymorphism, which affects IgG binding affinity, is a risk factor for systemic lupus erythematosus (SLE).


METHODS
We genotyped a group of 70 Caucasian SLE patients for all known Fc gammaR polymorphisms. Of this group, 45 patients (64%) had nephritis. In 35 patients, this diagnosis was confirmed by renal biopsy.


RESULTS
In the total group of 70 SLE patients, the frequency of the Fc gammaRIIIA-158F allele was 0.74, versus 0.57 in healthy controls (P = 0.003). The genotype distribution of the Fc gammaRIIIA-158V/F polymorphism was also significantly different from that of the control population (P = 0.004). The distribution of the other Fc gammaR polymorphisms--Fc gammaRIIA-131R/H, Fc gammaRIIIB-NA(1,2), and Fc gammaRIIIA-48L/R/H--was similar in SLE patients and controls.


CONCLUSIONS
In our group of SLE patients, only the distribution of the alleles of the Fc gammaRIIIA-158V/F polymorphism was significantly different from that in the control group. This might indicate that macrophage expression of the Fc gammaRIIIA-158F isoform is involved in the disturbed clearance of immune complexes in patients with SLE.
Central Laboratory of The Netherlands Red Cross Blood Transfusion Service, and Academic Medical Center, University of Amsterdam.
H R
HR
Koene
M
M
Kleijer
A J
AJ
Swaak
K E
KE
Sullivan
M
M
Bijl
M A
MA
Petri
C G
CG
Kallenberg
D
D
Roos
A E
AE
von dem Borne
M
M
de Haas
D000483:Alleles; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000235:genetics*; D008181:Lupus Nephritis / Q000235:genetics; D011110:Polymorphism, Genetic; D017452:Receptors, IgG / Q000235:genetics*; D044465:White People / Q000235:genetics
D017452:Receptors, IgG