Lack of Association between Angiotensin Converting Enzyme I/D Polymorphism and Unexplained Recurrent Miscarriage in Saudi Arabia.

Background: An insertion/deletion (I/D) polymorphism in the angiotensin converting enzyme (ACE) gene has been associated with recurrent miscarriage (RM) in several populations. We initiated this study to determine the association, if any, between the I/D polymorphism of ACE gene and RM in Saudi females.

Method: This study was conducted on 61 Saudi females suffering from RM (mean age: 34.1±6.2 years; range 15-45) attending clinics at King Khalid University Hospital, and 59 age matched females who had at least 2 children, as controls. Blood samples were drawn in EDTA tubes by venipuncture. DNA was extracted using the Puregene DNA purification kits. Insertion/Deletion (I/D) polymorphism of ACE gene was investigated by amplifying the genomic DNA by PCR using gene-specific primers. A single 190 bp or 490 bp band was obtained in the homozygous cases for the D allele or I allele, respectively, while the presence of both 190 and 490 bp bands indicated heterozygosity (ID).

Statistical Analysis: Deviation from Hardy-Weinberg equilibrium was determined (http://ihg.gsf.de/cgi-bin/hw/hwa1.pl). A standard chi-square (χ) test was used for comparing the genotype and allele frequencies in the two groups and Students't' test and χ test were employed to compare values between the two groups. P<0.05 was considered statistically significant.

Results: The frequencies of DD, ID, and II genotypes were 56.7%, 29.5% and 4.9%, respectively, in females with RM and 54.2%, 42.3% and 3.3% respectively in the control group, but the difference was not statistically significant.

Conclusion: In some populations, meta-analyses showed an association between I/D polymorphism and RM risk, and the D allele was implicated as an increased risk factor for RM. However, this association was not apparent in the Saudi females.