Table 1 Frequency of genotypes expressing low levels of mannan‐binding lectin and C4AQ0 in all the nine multicase families with systemic lupus erythematosus.

	Patients with SLE n = 24 (%)	First‐degree relatives n = 83 (%)	Second‐degree relatives n = 23 (%)	p*	p†	Family controls n = 24 (%)	p‡	p§
Low MBL genotypes	38	26	13	0.16	0.057	33	0.25	0.57
C4AQ0	50	47	39	0.73	0.46	25	0.23	0.045
Low MBL with C4AQ0	21	13	0	0.086	0.030	4	0.079	0.021

MBL, mannan‐binding lectin, SLE, systemic lupus erythematosus.

*χ² test for independence between patients with SLE, first‐degree relatives and second‐degree relatives.

†χ² test for trend between patients with SLE, first‐degree relatives and second‐degree relatives.

‡χ² test for independence between patients with SLE, relatives and family controls.

§χ² test for trend between patients with SLE, relatives and family controls.