A Systematic Review and Meta-Analysis for the Association of Gene Polymorphisms in RAN with Cancer Risk

Table 1

The characteristics of eligible studies.

Ref. no.	Year	Country	Ethnicity	Sample size		Source of controls	Genotyping method	Adjustment factors	Quality score	Citation
				Case	Control
1	2008	America	Caucasian	746	746	PB	SNPlex assay	Age, gender, and smoking status	8.5	[14]
2	2008	America	Caucasian	279	278	PB	SNPlex technology	Age, gender, and smoking status	7.5	[15]
3	2010	Korea	Asian	100	100	HB	Sequenome mass spectrometry-based genotyping assay	NM	7	[16]
4	2012	China	Asian	560	560	PB	PCR-RFLP	Gender, age, drinking status, smoking status, and family history of cancer	9.5	[30]
5	2012	China	Asian	397	900	PB	TaqMan allelic discrimination assay	Age, sex, smoking status, and alcohol status	9.5	[31]
6	2013	China	Asian	1300	2688	PB	TaqMan allelic discrimination assay	Age, sex, smoking status, and drinking status	9.5	[17]
7	2013	China	Asian	1486	1549	PB	TaqMan allelic discrimination assay	Age, age at menarche, menopausal status, and parity	9.5	[32]
8	2013	China	Asian	1792	1867	PB	TaqMan OpenArray genotyping system/TaqMan assay	Age, age at menarche, and menopausal status	10	[29]
9	2015	Korea	Asian	408	400	HB	PCR-RFLP	Age, gender, hypertension, and diabetes mellitus	5	[33]
10	2015	Poland	Caucasian	135	170	HB	TaqMan SNP genotyping assay	NM	5.5	[34]
11	2016	Korea	Asian	147	229	PB	PCR-RFLP	Age, gender, hypertension, diabetes mellitus, drinking status, and smoking	5.5	[35]
12	2017	China	Asian	312	320	HB	TaqMan SNP genotyping assay	Age, gender, smoking status, alcohol intake, hepatitis B/C virus infection, and fatty liver/nonalcoholic hepatitis status	7	[36]

Note: PB, population-based; HB, hospital-based; PCR-RFLP, in reaction-restriction fragment length polymorphism; NM, not mentioned.