Paraoxonase gene polymorphisms and plasma oxidized low-density lipoprotein level as possible risk factors for exudative age-related macular degeneration.
OBJECTIVE
Paraoxonase (E.C.3.1.1.2) is a polymorphic protein shown to prevent low-density lipoprotein oxidation. Our purpose is to evaluate the hypothesis that paraoxonase gene polymorphisms and plasma oxidized low-density lipoprotein level play a role in the occurrence of exudative age-related macular degeneration.


METHODS
We analyzed paraoxonase genotypes (A/B, Gln-Arg192 and L/M, Leu-Met54) and plasma oxidized low-density lipoprotein levels in 72 unrelated Japanese patients with exudative age-related macular degeneration and compared the results with those of 140 age-matched and sex-matched control subjects.


RESULTS
The distribution of paraoxonase 192 and paraoxonase 54 polymorphisms was significantly different between the patients with age-related macular degeneration and control subjects (chi-square = 6.226, P =.0445, and chi-square = 6.863, P =.0323, respectively). The high frequency of the BB genotype at position 192 was observed in the exudative age-related macular degeneration group compared with control subjects (52.8% vs 35.0%, respectively; P =.0127). The high frequency of the LL genotype at position 54 was observed in the patients more than the controls (91.7% vs 77.1%, respectively; P =.0090). The mean (+/- SE) oxidized low-density lipoprotein levels in the patients was significantly higher than in the controls (19.1 +/- 1.0 vs 16.2 +/- 0.6 U/ml, P <.01).


CONCLUSIONS
These results indicate that the paraoxonase gene polymorphisms may represent a possible genetic risk factor for age-related macular degeneration and that increased plasma oxidized low-density lipoprotein may be involved in the pathogenesis of age-related macular degeneration.
Ikeda
T
T
Department of Ophthalmology, Osaka Medical College, Osaka, Japan. tikeda@ophth.kpu-m.ac.jp
Obayashi
H
H
Hasegawa
G
G
Nakamura
N
N
Yoshikawa
T
T
Imamura
Y
Y
Koizumi
K
K
Kinoshita
S
S
D000368:Aged; D043303:Aryldialkylphosphatase; D004247:DNA / Q000032:analysis; D004950:Esterases / Q000235:genetics*; D005122:Exudates and Transudates; D005260:Female; D005838:Genotype; D006801:Humans; D008077:Lipoproteins, LDL / Q000097:blood*; D008268:Macular Degeneration / Q000097:blood* / Q000235:genetics*; D008297:Male; D011110:Polymorphism, Genetic; D012307:Risk Factors
D008077:Lipoproteins, LDL; C099252:oxidized low density lipoprotein; D004247:DNA; D004950:Esterases; D043303:Aryldialkylphosphatase