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 (χ2) test was used for comparing the genotype and allele frequencies in the two groups and Students't' test and χ2 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.
Uvod: Insercioni/delecijski polimorfizam (I/D) u genu za AKE (angiotenzin-konvertujući enzim) doveden je u vezu sa višestrukim spontanim pobačajima (VSP) u nekoliko populacija. Ovu studiju smo sproveli kako bismo utvrdili da li postoji ili ne postoji povezanost između I/D polimorfizma gena za AKE i VSP kod žena u Saudijskoj Arabiji.
Metod: Studija je obuhvatila 65 žena saudijske nacionalnosti sa VSP (prosek godina: 34,1±6,2 godina; raspon 15–45) koje su se lečile na klinikama Univerzitetske bolnice kralj Halid i 65 žena iste starosne dobi koje su imale najmanje dvoje dece, kao kontrolnu grupu. Uzorci krvi sakupljani su u EDTA epruvete venepunkcijom. DNK je ekstrahovana pomoću Puregene DNA purification kitova. Insercioni/delecijski (I/D) polimorfizam gena za AKE je ispitivan putem amplifikacije genomske DNK pomoću PCR uz korišćenje prajmera specifičnih za gene. U slučaju homozigota za D alel ili I alel dobijana je po jedna traka duga 190 bp ili 490 bp, dok je prisustvo obe trake od 190 i 490 bp značilo heterozigotnost (ID).
Statistička analiza: Procenjeno je odstupanje od Hardi-Vajnbergove ravnoteže. Za poređenje učestalosti genotipova i alela u dve grupe korišćen je standardni hi-kvadratni test (c2), dok su za poređenje vrednosti između dve grupe primenjeni studentov T test i c2 test. P < 0,05 smatrano je statistički značajnim.
Rezultati: Učestalosti DD, ID i II genotipova bile su 56,7%, 29,5% i 4,9% kod žena sa VSP, odnosno 54,2%, 42,3% i 3,3% u kontrolnoj grupi, ali razlika nije bila statistički značajna.
Zaključak: U nekim populacijama metaanalize su pokazale povezanost između I/D polimorfizma i rizika za VSP, ali D alel je bio umešan kao faktor povećanog rizika za VSP. Međutim, ova povezanost nije bila ispoljena kod saudijskih žena.
Keywords: ACE polymorphism; habitual abortion; recurrent miscarriage; recurrent pregnancy loss; renin–angiotensin system.