Table 1.

The essential characteristics of the studies we included

Authors	Year	Country	Continent	Race	Eligible	Subjects	Method
					Cases	Controls
C. Fatini et al.	2000	Italy	Europe	Caucasian	59	70	PCR
T.Buchholz et al.	2003	Germany	Europe	Caucasian	184	127	PCR
Chelsi Goodman et al.	2009	USA	North America	Caucasian	120	84	PCR
Rami J. Al Sallout et al.	2010	Gaza Strip	Asia	Asian	100	100	PCR
MORTEZA BAGHERI et al.	2010	Iran	Asia	Asian	50	63	PCR
R. M. Corbo et al.	2011	Italy	Europe	Caucasian	18	69	PCR
MAHMOUD AARABI et al.	2011	Iran	Asia	Asian	63	94	PCR
Shufang Zhang, MS et al.	2011	China	Asia	Asian	127	132	PCR
Ozturk Ozdemir et al.	2011	Turkey	Asia	Caucasian	543	106	PCR