Genotyping analyses for polymorphisms of ANXA5 gene in patients with recurrent pregnancy loss.

OBJECTIVE: To investigate whether polymorphisms at the promoter or 5'-untranslated region of annexin A5 gene (ANXA5) influence miscarriage.
DESIGN: Case-control study and nested case-control study.
SETTING: Hospitals. PATIENT(S): A total of 264 patients with two to nine recurrent pregnancy losses (RPLs) and 195 fertile control subjects. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The frequency of six single-nucleotide polymorphisms (SNPs) of the ANXA5 gene in RPL patients versus control subjects, and subsequent live birth rate with and without risk alleles in RPL patients. RESULT(S): The minor allele was significantly more frequent in RPL patients than in control subjects for SNP5 (rs1050606). The live birth rates of patients with and without risk alleles of SNP5 were 84.0% and 84.3%, respectively, after excluding cases with abnormal embryonic karyotype, with no significant difference. CONCLUSION(S): The variations with the ANXA5 gene upstream region, especially SNP5, were confirmed to be risk factors of RPL. However, presence/absence of the ANXA5 risk allele did not have any predictive effect for subsequent pregnancy outcome. This was the first study indicating the influence of ANXA5 SNP5 for pregnancy outcome.