The rs74794265 SNP of the SREK1 Gene is Associated with COPD in Kashi, China

Figures & data

Table 1 Characteristics of the Study Population

Variable	Case n=541 (%)	Control n=534 (%)	P
Age (years) (mean ± SD)	61.11 ± 12.26	54.86 ± 10.73	< 0.001
Sex, n (%)			0.009
Male	280 (51.75)	234 (43.82)
Female	261 (48.24)	300 (56.18)
BMI (kg/m^2), (mean ± SD)	23.56 ± 4.22	25.55 ± 4.17	< 0.001
Annual household income (CNY, yuan) (mean ± SD)	16,939 (10,294–23,442)	15,298 (9762–23,057)	0.197
Smoking status, n (%)			< 0.001
Yes	124 (22.92)	69 (12.92)
No	417 (77.07)	465 (87.08)
Smoking index^a, n (%)			< 0.001
≤ 1	417 (77.07)	465 (87.08)
1 ≤ SI ≤ 400	98 (18.11)	52 (9.74)
400 < SI ≤ 800	16 (2.97)	11 (2.06)
SI > 800	10 (1.85)	6 (1.12)
Coal combustion, n (%)
Yes	513 (94.82)	516 (96.63)	0.144
No	28 (5.18)	18 (3.37)
Charcoal combustion, n (%)
Yes	519 (95.93)	500 (93.63)	0.09
No	22 (4.07)	34 (6.37)
Lung function (mean ± SD)
FEV1%	69.00 (53.92–82.00)	86.00 (74.00–98.00)	< 0.001
FEV1/FVC	0.602 (0.55–0.66)	0.80 (0.75–0.86)	< 0.001

Note: ^aSI= number × year.

Abbreviation: BMJ, Body Mass Index.

Table 2 HWE Analysis

	Type	HOMA	HET	HOMR	HWE
	Genotype	T/T	C/T	C/C
rs74794265 (SREK1)	All	0	28	1041	1
	Case	0	8	527	1
	Control	0	20	514	1

Abbreviation: HWE, Hardy–Weinberg’s equilibrium test.

Table 3 Analysis of Genotypes of Rs74794265

SNP	Model	Genotype	Case	Control	OR (95% CI)	P value
rs74794265 (SREK1)	Additive	T/T	0	0	0.3677 (0.1547–0.8742)	0.02355*
		C/T	8	20
		C/C	527	514
	Dominant	T/T, C/T	8	20	0.3677 (0.1547–0.8742)	0.02355*
		C/C	527	514
	Recessive	T/T	0	0	NA (NA–NA)	NA
		C/C, C/T	535	534
	Allele	T	8	20	0.3728 (0.1577–0.8811)	0.02455*
		C	1062	1048

Notes: Logistic regression: corrected sex, age, and BMI; *P<0.05.

Abbreviations: OR, Odds ratio; 95% CI, 95% confidence interval.

Table 4 SNP of Rs74794265 Among Smokers

SNP	Model	Genotype	Case	Control	OR (95% CI)	P value
rs74794265 (SREK1)	Additive	T/T	0	0	0.6244 (0.0304–12.83)	0.76
		C/T	1	1
		C/C	122	68
	Dominant	T/T, C/T	1	1	0.6244 (0.0304–12.83)	0.76
		C/C	122	68
	Recessive	T/T	0	0	NA	NA
		C/C, C/T	123	69
	Allele	T	1	1	0.6279 (0.0311–12.68)	0.7615
		C	245	137

Abbreviations: OR, Odds ratio; 95% CI, 95% confidence interval.

Table 5 SNP of Rs74794265 in No Smokers

SNP	Model	Genotype	Case	Control	OR (95% CI)	P-value
rs74794265 (SREK1)	Additive	T/T	0	0	0.3217 (0.1156–0.8949)	0.02981*
		C/T	5	19
		C/C	367	446
	Dominant	T/T, C/T	5	19	0.3217 (0.1156–0.8949)	0.02981*
		C/C	367	446
	Recessive	T/T	0	0	NA	NA
		C/C, C/T	372	465
	Allele	T	5	19	0.3267 (0.1181–0.9036)	0.03115*
		C	739	911

Note: *P<0.05.

Abbreviations: OR, Odds ratio; 95% CI, 95% confidence interval.