title: [Relationship between genetic polymorphisms of matrix metalloproteinase-2 and -3 and susceptibility to silicosis].
abstract: OBJECTIVE
  To investigate the relationship between the genetic polymorphisms of matrix metalloproteinase-2 (MMP-2) (-735) and matrix metalloproteinase-3 (MMP-3) (-1171) and the susceptibility to silicosis.
  
  
  METHODS
  A case-control study was conducted in 113 patients diagnosed with stage I silicosis (case group) and 115 dust-exposed workers without silicosis (control group); the two groups had the same sex, ethnic group, and type of dust and similar age and cumulative exposure time. Polymerase chain reaction-restriction fragment length polymorphism was used to determine the genotypes of MMP-2 (-735) and MMP-3 (-1171).
  
  
  RESULTS
  No significant difference was observed in age, cumulative exposure time, or smoking rate between cases and controls (P > 0.05). The frequencies of genotypes C/C, C/T, and T/T at MMP-2 C-735T in the case group were 57.5% (65/113), 31.0% (35/113), and 11.5% (13/113), respectively, which were significantly different from those of the control group (69.6% (80/115), 26.9% (31/115), and 3.5% (4/115)), χ² = 6.542, P < 0.05). The frequencies of T allele in cases and controls were 27.0% and 17.0%, respectively, which were significantly different from each other χ² = 6.704, P < 0.05). Carriage of T allele at MMP-2 C-735T increased the risk of silicosis (OR = 1.811, 95% CI: 1.151-2.847). The frequencies of genotypes 6A/6A, 5A/6A, and 5A/5A at MMP-3 A-1171A were 67.2% (76/113), 24.8% (28/113), and 8.0% (9/113), respectively, in the case group, versus 59.1% (68/115), 37.4% (43/115), and 3.5% (4/115) in the control group (χ² = 5.519, P > 0.05).
  
  
  CONCLUSIONS
  Genetic polymorphism at MMP-2 C-735T is significantly associated with the development of silicosis. Carriage of T allele increases the risk of silicosis among workers exposed to dust. No significant association was found between MMP-3 A-1171A polymorphism and silicosis in this study.
authors.affiliation: School of Public Health, Hebei United University, Tangshan, Hebei Province 063000, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Kou
authors.affiliation: School of Public Health, Hebei United University, Tangshan, Hebei Province 063000, China. E-mail: xueyun53@163.com.
authors.forename: Xueyun
authors.initials: X
authors.lastname: Fan
authors.affiliation: School of Public Health, Hebei United University, Tangshan, Hebei Province 063000, China.
authors.forename: Yaxin
authors.initials: Y
authors.lastname: Shi
authors.affiliation: School of Public Health, Hebei United University, Tangshan, Hebei Province 063000, China.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Wang
authors.affiliation: School of Public Health, Hebei United University, Tangshan, Hebei Province 063000, China.
authors.forename: Fuhai
authors.initials: F
authors.lastname: Shen
authors.affiliation: School of Public Health, Hebei United University, Tangshan, Hebei Province 063000, China. E-mail: yulanjin225@qq.com.
authors.forename: Yulan
authors.initials: Y
authors.lastname: Jin
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D020778:Matrix Metalloproteinase 2 / Q000235:genetics*; D019278:Matrix Metalloproteinase 3 / Q000235:genetics*; D008875:Middle Aged; D011110:Polymorphism, Genetic; D012829:Silicosis / Q000235:genetics*
chemical_list: C511768:MMP3 protein, human; D019278:Matrix Metalloproteinase 3; C522361:MMP2 protein, human; D020778:Matrix Metalloproteinase 2