The Association Between GC Gene Polymorphisms and Metabolic Syndrome in Chinese Rural Population: A Case–Control Study

Figures & data

Table 1 Information on the Selected SNPs in GC Gene

SNPs	Allele	Position	Location	MAF^a
rs7041	T>G	4:71752617	Exon	0.382
rs4588	C>A	4:71752606	Exon	0.208
rs2282679	A>C	4:71742666	Intron	0.202
rs705117	G>A	4:71742398	Intron	0.422

Note: All SNP information from NCBI database GRCh38. p7.

Abbreviation: SNP, Single nucleotide polymorphism; ^aMAF, minor allele frequencies based on 1000 Genomes Project.

Table 2 Anthropometric and Clinical Characteristics of Study Participants

Characteristics	MetS (n=445)	Control (n=445)	P
Male	194(43.60%)	194(43.60%)	1
Age (years)	56.00(46.00–66.00)	55.00(46.00–65.00)	0.963
Smoking	98(22.02%)	113(25.39%)	0.237
Drinking	60(13.48%)	60(13.48%)	1
Family history of diabetes	99(22.25%)	84(18.88%)	0.426
Family history of hyperlipidemia	39(8.76%)	26(5.84%)	0.214
Family history of obesity	16(%)3.60	9(2.02%)	0.306
Family history of hypertension	177(39.78%)	156(35.06%)	0.194
BMI (kg/m^2)	27.63(25.93–29.79)	24.30(22.09–26.59)	<0.01
WC (cm)	95.00(90.00–100.00)	84.00(77.00–90.00)	<0.01
FPG (mg/dl)	5.44(4.57–7.17)	4.64(4.07–5.17)	<0.01
TC (mg/dl)	4.51(3.95–5.28)	4.43(3.90–5.13)	0.015
TG (mg/dl)	1.97(1.36–2.68)	1.06(0.71–1.46)	<0.01
HDL-C (mg/dl)	1.21(1.03–1.39)	1.46(1.28–1.65)	<0.01
LDL-C (mg/dl)	2.33(1.90–3.03)	2.49(2.04–2.99)	0.080
SBP (mm Hg)	133.00(123.00–148.00)	123(115.00–137.00)	<0.01
DBP (mm Hg)	85.00(80.00–92.00)	80.00(75.00–88.00)	<0.01
VDBP (μg/mL)	136.40(103.99–284.79)	145.97(100.88–336.99)	0.735

Note: Data are displayed as medians (interquartile range) or numbers (%).

Abbreviations: BMI, body mass index; WC, waist circumference; FPG, fasting plasma glucose; TC, total cholesterol; TG, triglyceride; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol; SBP, systolic blood pressure; DBP, diastolic blood pressure; VDBP, vitamin D binding protein.

Figure 1 Genotypic distributions of single nucleotide polymorphisms in the GC gene among MetS patients and controls. The total number in each group is not equal to 445 because of failed genotyping for some samples. Data are presented as count numbers and percentages. (A) Frequencies of rs7041, (B) frequencies of rs4588, (C) frequencies of rs2282679, and (D) frequencies of rs705117. The P-values were generated by Pearson’s χ² tests.

Table 3 Associations of Genotypes of GC Gene and Risk of Metabolic Syndrome in Han Chinese

SNPs	Genotypes	Adjusted ORs^a	95% CI	P
rs7041	TT	1
	TG	1.103	0.830–1.465	0.501
	GG	1.367	0.807–2.313	0.245
	TG+GG/TT	1.142	0.870–1.479	0.339
	GG/TT+TG	1.310	0.785–2.186	0.301
rs4588	CC	1
	CA	0.678	0.505–0.910	0.010
	AA	0.603	0.373–0.973	0.039
	CA+AA/CC	0.663	0.503–0.875	0.004
	AA/CC+CA	0.751	0.478–1.178	0.212
rs2282679	AA	1
	AC	0.683	0.509–0.917	0.011
	CC	0.668	0.416–1.073	0.095
	AC+CC/AA	0.683	0.519–0.897	0.006
	CC/AA+AC	0.774	0.494–1.214	0.264
rs705117	GG	1
	GA	0.821	0.580–1.162	0.265
	AA	0.689	0.470–1.008	0.055
	GA+AA/GG	0.769	0.560–1.005	0.103
	AA/GG+GA	0.781	0.571–1.068	0.122

Note: ^aAdjusted for smoking status, drinking status, family history of diabetes, family history of hypertension, family history of hyperlipidemia, and family history of obesity.

Abbreviations: OR, odds ratio; SNP, single nucleotide polymorphism.

Figure 2 Association of genotypes of SNPs (rs7041, rs4588, rs2282679, and rs705117) of GC gene and risk of metabolic syndrome components in the rural population in Henan, China. (A) The associations between GC variants and high level of TG (triglycerides); (B) The associations between GC variants and low level of HDL-C (high-density lipoprotein-cholesterol); (C) The associations between GC variants and high level of SBP (systolic blood pressure); (D) The associations between GC variants and high level of DBP (diastolic blood pressure); (E) The associations between GC variants and high level of FPG (fasting plasma glucose); (F) The associations between GC variants and high level of WC (waist circumference).

Notes: ^aAdjusted for smoking status, drinking status, family history of diabetes, family history of hypertension, family history of hyperlipidemia, and family history of obesity. ^bStudy subjects who took lipid-lowering medicine two weeks before the survey were excluded from the statistical analysis process. ^cStudy subjects who took hypotensive drugs two weeks before the survey were excluded from the statistical analysis process. ^dStudy subjects who took anti-diabetic agents two weeks before the survey were excluded from the statistical analysis process.

Table 4 Associations Between GC Gene and Level of VDBP

SNP	Level of VDBP^a	P
rs7041		0.133
TT	140.37(101.33–345.43)
TG	134.28(100.29–268.26)
GG	158.10(109.42–378.46)
rs4588		0.052
CC	149.75(103.40–361.81)
CA	129.86(100.05–276.37)
AA	153.52(106.18–336.58)
rs2282679		0.042
AA	150.91(103.92–397.11)
AC	129.47(100.18–276.73)
CC	137.08(101.33–282.53)
rs705117		0.145
GG	151.50(103.94–423.85)
GA	132.14(98.81–283.09)
AA	143.09(105.56–282.53)

Note: ^aThe level of VDBP was expressed as medians with a corresponding interquartile range.

Table 5 Association and Risk Between the Level of VDBP and MetS

Level of VDBP^a	Control	MetS	χ^2	P	OR (95% CI)	P
VDBP-L	325(73.03%)	338(75.96%)	2.078	0.354	1
VDBP-M	61(13.71%)	47(10.56%)			0.735(0.505–1.122)	0.163
VDBP-H	59(13.26%)	60(13.48%)			0.983(0.661–1.464)	0.934

Note: ^aRange for levels of VDBP were defined as follows: VDBP-L (<300μg/mL); VDBP-M (300–600μg/mL); VDBP-H (>600μg/mL).