Polymorphisms in the Endothelial Nitric Oxide Synthase Gene May Be Protective Against Preeclampsia in a Chinese Population

The association between the endothelial nitric oxide synthase (eNOS) gene with vascular diseases in Western populations and with severe preeclampsia (PE) in the Japanese population have been demon-strated, lacing the data in Chinese population. The authors examine the association between PE and 2 polymorphisms of the eNOS gene in a Chinese population, consisting of 92 pregnant women with PE and 256 healthy controls. All were genotyped for the Glu298Asp polymorphism in exon 7 and the number of 27 base pair repeats in intron 4 of the eNOS gene. The frequencies of both the variant T allele and eNOS 4a (small allele with 4 repeats of 27 bp) were significantly lower in the PE group than in the control group. The genotype distribution of Glu298Glu, Glu298Asp, and Asp298Asp in eNOS exon 7 and bb type and ab type in eNOS intron 4 revealed statistically significant differ-ences between control and PE groups. This is the first study to evaluate the association between 2 poly-morphisms in the maternal eNOS gene with PE simultaneously in a Chinese population. Similar to the findings in Western populations, polymorphisms in the eNOS gene may be protective against PE in a Chinese population, in contrast to the results in the Japanese population. KEY WORDS: endothelial nitric oxide synthase, preeclampsia, polymorphism, Chinese population