Contribution of VEGF polymorphisms to variation in VEGF serum levels in a healthy population.

OBJECTIVE: Vascular endothelial growth factor (VEGF) is a pro-angiogenic factor. Variability in VEGF expression, induced by specific VEGFA variants, are involved in angiogenesis-related disorders. This study examined the genotype distribution and functional role (VEGF expression) of rs699947, rs833061, rs1570360, rs2010963, rs833068, rs833070, rs3025020, and rs3025039 VEGFA variants and their haplotypes in 519 healthy Bahraini individuals of both genders. METHODS AND RESULTS: The distribution of the eight VEGFA polymorphisms screened was in Hardy-Weinberg equilibrium. The minor allele frequencies of rs699947 (0.42), rs833061 (0.32), rs1570360 (0.31), rs2010963 (0.33), rs833068 (0.37), rs833070 (0.42), rs3025020 (0.33), and rs3025039 (0.13) were generally compared to those established for Caucasians. Of the variants tested, rs3025020 was associated with increased VEGF serum levels (p=0.019), while rs3025039 was associated with decreased levels (p=0.038). Linkage analysis identified two VEGFA blocks, the first, spanning 16 kb, was not associated with altered VEGF levels, while the second, spanning 3 kb containing rs3025020 and rs3025039, was linked with higher VEGF expression, of which the (-583)T/(+936)T haplotype (p=0.008) was linked with higher VEGF levels compared to the (-583)C/(+936)C (all wild-type) haplotype. CONCLUSION: These results support the association of rs30250202 and rs3025039, and specific VEGF haplotypes, with altered VEGF serum levels, although the exact functional mechanisms remain to be elucidated.

Analysis of interleukin-18 promoter polymorphisms and changes in interleukin-18 serum levels underscores the involvement of interleukin-18 in recurrent spontaneous miscarriage.

OBJECTIVE: To evaluate the association of interleukin-18 (IL-18) promoter single-nucleotide polymorphisms rs1946519 (-656C/A), rs187238 (-137G/C), rs360718 (-119A/C), and rs360717 (-105G/A) and changes in IL-18 serum levels with recurrent spontaneous miscarriage (RSM). DESIGN: Case-control study. SETTING: Outpatient obstetrics and gynecology clinics. PATIENT(S): Women with confirmed RSM (n = 282), and 283 age- and ethnically matched controls. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): IL-18 genotyping was accomplished by allelic discrimination assays; serum IL-18 levels were measured by ELISA. RESULT(S): The minor allele frequencies of rs360717 and rs1946519, but not rs360718 or rs187238, were higher in patients with RSM. Significant differences in the distribution of the rs360717 and rs1946519 genotypes were noted between patients and controls, and both rs360717 and rs1946519 IL-18 single-nucleotide polymorphisms showed significant association with RSM under additive, dominant, and recessive models. Lower serum IL-18 levels were seen between patients and controls and were more pronounced in rs360717 and rs1946519 heterozygous and homozygous genotypes. Four-locus (rs1946519/rs187238/rs360718/rs360717) IL-18 haplotype analysis identified that the AGAA (Pc<.001), CGAA (Pc<.001), and ACAG (Pc=.018) haplotypes were associated with a reduction in IL-18 secretion and with increased RSM risk, after adjustments for body mass index, menarche, and gravida. CONCLUSION(S): These results demonstrated that reduced IL-18 levels and rs360717 and rs1946519 IL-18 variants are significantly associated with RSM.

Genetic variations in the interleukin-21 gene and the risk of recurrent idiopathic spontaneous miscarriage.

OBJECTIVES: Insofar as recurrent spontaneous miscarriage (RSM) is linked with dysregulated immunity and inflammatory changes, and given the pro-inflammatory role of interleukin-21 (IL-21), we examined the association between IL-21 polymorphisms and RSM. METHODS AND RESULTS: IL-21 rs2055979, rs13143866, rs9992580, and rs4833837 were genotyped in 235 cases of RSM and 235 controls. Regression analysis was employed in assessing the contribution of IL-21 variants to the overall RSM risk. Higher minor allele and genotype frequencies of rs2055979 and rs13143866, but not rs9992580 or rs4833837, were seen in RSM patients than in the controls. IL-21 haplotype [rs9992580/rs4833837/rs2055979/rs13143866] analysis revealed a lower frequency of the TGCG haplotype, and a higher frequency of the GGCG and GAAA haplotypes in patients, thus conferring protection from or a susceptibility to RSM by these haplotypes respectively. Regression analysis confirmed the association of TGCG [OR (95%CI)=0.09 (0.05-0.16)], and GGCG [OR (95%CI)=2.52 (1.34-4.54)] and GAAA [OR (95%CI)=4.02 (2.20-7.70)] haplotypes, after adjusting for age and BMI. CONCLUSIONS: Our findings indicate that IL-21 is a novel susceptibility gene for RSM.

Anti-annexin V IgM and IgG autoantibodies and the risk of idiopathic recurrent spontaneous miscarriage.

Anti-annexin V antibodies have been identified as risk factors for recurrent spontaneous miscarriage (RSM) in some, but not all previous studies. We investigated the association between anti-annexin IgM and IgG in RSM cases and control women. Blood samples from 244 women with idiopathic RSM, and 283 multi-parous control women were tested for anti-annexin V antibodies by ELISA. A significant elevation in anti-annexin V IgM and IgG was seen in the RSM cases. An increased prevalence of elevated anti-annexin V IgM and to a lesser extent anti-annexin V IgG was seen in RSM patients. Receiver operating characteristic analysis indicated that the area under the curve for anti-annexin V IgM was 0.916, and for anti-annexin V IgG was 0.725. A systematic shift in anti-annexin V IgM and IgG distributions toward higher values occurred in RSM women, which was confirmed by percentile analysis. For each of the anti-annexin V isotypes, the adjusted odds ratio increased as the percentile value increased; the strongest risk was for anti-annexin V IgM, in which the 99th percentile (P99) was associated with a 165-fold higher risk than P50, and for anti-annexin V IgG where P99 was associated with a 38-fold higher risk than P50. In addition, a higher prevalence of elevated anti-annexin V IgM and anti-annexin V IgG was seen in RSM cases than in control women. We conclude that anti-annexin V IgM and IgG antibody positivity are independent risk factors for RSM.

Effect of the functional VEGFA-583C/T variant on vascular endothelial growth factor levels and the risk of recurrent spontaneous miscarriage.

The association of vascular endothelial growth factor (VEGF) -583C/T variant with recurrent miscarriage (RSM) was investigated in 173 RSM cases and 248 control women. Increased minor allele and genotype frequencies of -583C/T, and reduced serum VEGF concentrations were associated with increased risk of RSM.

Common polymorphisms of calpain-10 and the risk of Type 2 Diabetes in a Tunisian Arab population: a case-control study.

BACKGROUND: Genetic variations in the calpain-10 gene (CAPN10), in particular the at-risk diplotype (112/121), were previously implicated with increased risk of type 2 diabetes (T2D). METHODS: We examined the association of CAPN10 UCSNP-43 (rs3792267), UCSNP-19 (rs3842570), and UCSNP-63 (rs5030952) SNPs with T2D in 917 Tunisian T2D patients and 748 non-diabetic controls. CAPN10 genotyping was done by PCR-RFLP. RESULTS: Enrichment of UCSNP-19 2R (minor) allele and 2R/2R genotype was found in T2D patients; the allele and genotype distribution of UCSNP-43 and UCSNP-63 alleles and genotypes were not significantly different between patient groups and non-diabetic control subjects. Regression analysis demonstrated progressive increases in T2D risk in 3R/2R [OR (95% CI) = 1.35 (1.08 - 1.68)] and 2R/2R [OR (95% CI) = 1.61 (1.20 - 2.18)] genotypes. Of the six haplotypes detected, enrichment of haplotype 111 (UCSNP-43/UCSNP-19/UCSNP-63) was seen in patients (Pc = 0.034); the distribution of the other haplotypes was comparable between patients and control subjects; neither haplotype 211 nor haplotype 212 was observed. Furthermore, the frequency of all CAPN10 diplotypes identified, including the "high-risk diplotype (112/121) reported for Mexican-Americans and Northern Europeans, were comparable between patients and controls. CONCLUSIONS: CAPN10 UCSNP-19 variant, and the 111 haplotype contribute to the risk of T2D in Tunisian subjects; no significant associations between CAPN10 diplotypes and T2D were demonstrated for Tunisians.