Objective   To explore the associations between glucokinase(GCK)gene, cytotoxic T cell antigen-4(CTLA-4) gene and gestational diabetes mellitus(GDM).

  Methods   A hospital-based 1:4 matched case-control study was conducted.Each GDM case was matched with four controls on age.21 GDM cases and 84 pregnant women without GDM were recruited.The mutations at exon6 and exon7 of GCK gene were determined by PCR-single-strand conformation polymorphism analysis.The mutations at exon1 and promoter of CTLA-4 gene were determined by PCR-restriction fragment length polymorphism analysis.A questionnaire was used to get the information about demographic characteristics, individuals and families.

  Results   Results form conditional logistic regression analysis showed that the A-G transition polymorphism at 49 position(exon1, codon17)(OR=4.510 95% CI 1.810~11.238)and the C-T transition polymorphism at position-318(promoter)of CTLA4 gene(OR=8.918 95% CI 1.558~51.040)was associated with the developent of GDM.The association between GCK gene and the develoment of GDM was not found.

  Conclusion   The A-G transition polymorphism at exonl and the C-T transition polymorphism at promoter of the CTLA4 gene were associated with higher risk for the development of GDM.