Table 2. Four IgG subclasses (mg/ml).

	n	IgG1	IgG2	IgG1/IgG2 ratio	IgG3	IgG4
Healthy controls
HLA-DQB1*0602 negative	13	6.76±1.23	4.07±1.30	1.80±0.58	0.30±0.11‡	0.49±0.19
HLA-DQB1*0602 positive	14	6.23±1.27	3.13±1.12	2.31±1.24	0.33±0.10‡	0.41±0.31♯
Narcolepsy
with normal range of IgG	13	6.15±1.06	3.73±1.56	1.96±0.90	0.40±0.14	0.82±0.50
with low IgG levels	10	4.65±2.42*	2.71±1.24†	2.40±2.11	0.28±0.16‡	0.59±0.63
Idiopathic hypersomnias	17	7.39±2.81	2.95±1.11†	2.67±0.93†	0.55±0.34†	0.92±1.12
Normal range estimated		4.30–9.22	1.46–6.68	0.65–2.96	0.07–0.55	0.11–0.88

*P<0.01 amongst healthy controls negative, positive for HLA-DQB1*0602 allele, narcolepsy with normal range of IgG and idiopathic hypersomnias.

^†The Value showed a raising/declining tendency against healthy controls negative for HLA-DQB1*0602 allele (P<0.03).

^‡P<0.03 against idiopathic hypersomnias.

^♯P<0.03 against narcolepsy patients with normal range of IgG.