HLA-G polymorphism and in vitro fertilization failure in a Polish population

• Published in: Tissue antigens Vol. 73; no. 4; pp. 348 - 352
• Main Authors: Sipak-Szmigiel, O., Cybulski, C., Wokołorczyk, D., Lubiński, J., Kurzawa, R., Bączkowski, T., Radwan, M., Radwan, P., Ronin-Walknowska, E.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01-04-2009
• Subjects: Abortion, Habitual - genetics; Abortion, Habitual - immunology; Alleles; European Continental Ancestry Group - genetics; Female; Fertilization in Vitro; Genotype; Histocompatibility Antigens Class I - genetics; Histocompatibility Antigens Class I - metabolism; HLA Antigens - genetics; HLA Antigens - metabolism; HLA-G; HLA-G Antigens; Humans; IVF; Male; Poland; polymorphism; Polymorphism, Genetic; Pregnancy; RNA, Messenger - metabolism; Poland
• ISSN: 0001-2815; 1399-0039
• DOI: 10.1111/j.1399-0039.2008.01205.x

To investigate whether human leukocyte antigen‐G (HLA‐G) gene polymorphism is associated with in vitro fertilization (IVF) failure, we sequenced exons 2–4 of the HLA‐G gene in 50 couples with three or more IVFs (including 10 couples with five or more IVFs) and 58 control fertile couples from a Polish population. Of the 10 different HLA‐G alleles identified in our study subjects, neither allele was found to be associated with IVF. We also genotyped 50 couples with IVF and 71 control couples for the −725C>G variant in the promoter region and the 14 bp insertion or deletion polymorphism in the 3′ untranslated region of the HLA‐G gene. The frequency of −725GG or GC genotype in women with IVF and in control fertile women was similar [26% vs 25.3%; odds ratio (OR) = 1.0; P = 1.0]. The 14 bp ins/ins or ins/del genotype was more common in women with IVF than in control women (76.9% vs 59.1%; OR 2.4; P = 0.03), but the difference was not significant after Bonferroni correction for multiple comparisons. The frequency of the ins/ins or ins/del genotype was particularly high (90%) in women who experienced five or more IVFs (OR = 6.2; P = 0.08), but again, the excess was not statistically significant, possibly because of small sample sizes. These results are in line with functional studies that show lower levels of HLA‐G mRNA and protein related to the HLA‐G allele including the 14 bp sequence and suggest that the insertion allele may be associated with an increased risk of IVF.