Cloning And Identifying Of Genes Associated With Pregnancy Induced Hypertension Syndrome

Pregnancy induced hypertension syndrome(PIHs), a common complication of pregnancy, the major cause of maternal morbidity and mortality in developing countries, is associated with abnormalities of placenta function due to shallow invasion of the maternal decidua by trophoblasts. The pathophysiology of PIHs is poorly understood. A few literatures prove that it is most unlikely that there is a single 'PIHs gene', so we are probably looking for a cluster of polymorphisms or changing in expression which, possibly in conjunction with environmental factors, predispose to the development of the condition, In this study ,we used PCR-based subtractive hybridization to clone placental genes related to PIHs and using other methods to identify them, and to explain their means in the etiopathology of PIHs.In this study, the placentae of PIHs and normotensive were used as models.Firstly, the cDNA Library was constructed and 33 fragments differentially expressing were cloned after a new version of PCR-based subtractive hybridization. Nine false positive clones were identified by reverse dot blot, and the rest 24clones were identified as PIHs related genes. Sequence analysis revealed that 19 clones were homologous to known genes , among which 9 genes or their products reportedly elevated in PIHs. These genes were HCG(No.8),HPLH(No.68),FN(81), mitochondrial(No.l3,14,17and 88), human hemoglobin gamma A(No.2) and hemoglobin bete(No.77). 7 genes had no report to back them to associate with PIHs. They were necdin-like gene(No.l), NADH dehydrogenase(No.l2),Rb gene(No.60), EF-1 alpha gene(No.62 and 66),ribosomal protein gene(No.71 and 84). The functions of other 3 genes were unclear. The 5 clones were identified as novel genes. These genes were acknowledged by GenBank. Their accession numbers are AF232216,AF232217,AF233648, AF361250, AF361251. Secondly, No.l andNo.5 genes were labeled 32P or digoxin as probes, placentae of 10 normal pregnant women and placentae of 10 PIHs patients were studied by using dot hybridization and in situ hybridization methods. The results of these two experiments were as follows: (1) Necdin-like and No.5-mRNAs were found in placenta! tissues of normal pregnancy as well as PIHs cases.(2) The intensity of transcription of necdin-like and No.S-mRNAs in placenta! tissues of PIHs cases increased significantly as compared with that of normal pregnancy( P<0.05) .(3)The transcriptions of necdin-like and No.S-mRNAs only occurred hi placenta! cytotrophoblast cells.We've cloned two groups of genes related to PIHs by subtractive hybridization. One group of genes reportedly related to PIHs, which provided that this method was practicable and effective, and supplied new molecular biologic basis for study results of pathogenesis and pathophysiology of PIHs. Another group of genes had no report to back them to associate with PIHs, which provided novel idea and way to study the pathogenesis of PIHs.