Apolipoprotein E polymorphisms in the development of hypertensive diseases of pregnancy in Korean women

Nam, Hwa; Kang, Ji Hyun; Jun, Jong Kwan

Abstract

OBJECTIVE
Hypertensive disorder in pregnancy is one of the most serious obstetrical complications. Apolipoprotein E (Apo E) genotype is polymorphic and recently it was reported to be associated with preeclampsia. We undertook this study to clarify whether polymorphic marker of apolipoprotein E is associated with the development of hypertensive disorder in pregnancy.
METHODS
Retrospective chart review was done. DNA was extracted from maternal blood of 124 healthy pregnant women and 253 women with hypertensive diseases in pregnancy. Hypertensive disorders complicating pregnancy include gestational hypertension (n=44), preeclampsia (n=158; mild=56, severe=102), preeclampsia superimposed preeclampsia (n=30), and chronic hypertension (n=21). Apo E allele was amplified by polymerase chain reaction, size fractionated on 4% agarose gels, and stained with ethidium bromide.
RESULTS
We found all six possible genotypes of Apo E. However, three genotypes, E2/2, E2/4 and E4/4, were uncommon in Korean. We analysed the data according to each allele. Allele frequencies of the Apo epsilon2, epsilon3 and epsilon4 were as follows: 6.8%, 83.0%, 10.2% in women with gestational hypertension, 4.5%, 84.8%, 10.7% in women with mild preeclampsia, 5.9%, 85.3%, 8.8% in women with severe preeclampsia, 1.7%, 91.7%, 6.7% in women with superimposed preeclampsia, 0.0%, 90.5%, 9.5% in women with chronic hypertension, and 5.2%, 86.5%, 8.5% in normal controls. No significant difference in Apo E alllele frequency was found among these groups (P>0.05).
CONCLUSIONS
The study suggests that specific allele of apolipoprotein E does not appear to be a risk factor for hypertensive disorders complicating pregnancy in Korean population.