Effects ofMTHFRc.677C>T,F2c.20210G>A andF5Leiden Polymorphisms in Gastroschisis

Effect of semaphorin 3C gene variants in multifactorial Hirschsprung disease

OBJECTIVE

Cluster genes, specifically the class 3 semaphorins (SEMA3) including SEMA3C, have been associated with the development of Hirschsprung disease (HSCR) in Caucasian populations. We aimed to screen for rare and common variants in SEMA3C in Indonesian patients with HSCR.

METHODS

In this prospective clinical study, we analyzed SEMA3C gene variants in 55 patients with HSCR through DNA sequencing and bioinformatics analyses.

RESULTS

Two variants in SEMA3C were found: p.Val337Met (rs1527482) and p.Val579 =  (rs2272351). The rare variant rs1527482 (A) was significantly overrepresented in our HSCR patients (9.1%) compared with South Asian controls in the 1000 Genomes (4.7%) and Exome Aggregation Consortium (ExAC; 3.5%) databases. Our analysis using bioinformatics tools predicted this variant to be evolutionarily conserved and damaging to SEMA3C protein function. Although the frequency of the other variant, rs2272351 (G), also differed significantly in Indonesian patients with HSCR (27.3%) from that in South Asian controls in 1000 Genomes (6.2%) and ExAC (4.6%), it is a synonymous variant and not likely to affect protein function.

CONCLUSIONS

This is the first comprehensive report of SEMA3C screening in patients of Asian ancestry with HSCR and identifies rs1527482 as a possible disease risk allele in this population.

Fetal gastroschisis: Maternal and fetal methylation profile

OBJECTIVE

The purpose of this study was to describe the genomic deoxyribonucleic acid (DNA) methylation profile in fetuses with gastroschisis, determine whether the profile was inherited, and investigate any possible correlations with maternal risk factors.

METHOD

Genome-wide DNA methylation analysis of 96 blood samples was performed using the Illumina Human Methylation 850K BeadChip. The blood samples were collected as follows: 32 from the umbilical cord of fetuses with gastroschisis, 32 from their respective mothers, 16 from the umbilical cord of fetuses without malformation, and 16 from their respective mothers.

RESULTS

The differential DNA methylation analysis showed a significant difference between the groups. The enrichment analysis resulted in 12 sites related to T-cell activation (p = 0.0128). The sites with different methylation status contained 10 genes, three of which were related to the beta-2-microglobulin gene. The methylation profile observed in the fetuses with gastroschisis was not inherited from the mothers. In addition, there was no association between maternal urinary tract infection, smoking, and alcohol use and different methylated sites.

CONCLUSION

We established the methylation profile of gastroschisis fetuses, which differs from that of normal fetuses. The profile was not inherited and did not correlate with maternal risk factors.

Aberrant Expressions and Variant Screening of SEMA3D in Indonesian Hirschsprung Patients

Background: The semaphorin 3D (SEMA3D) gene has been implicated in the pathogenesis of Hirschsprung disease (HSCR), a complex genetic disorder characterized by the loss of ganglion cells in varying lengths of gastrointestinal tract. We wished to investigate the role of SEMA3D variants, both rare and common variants, as well as its mRNA expression in Indonesian HSCR patients. Methods: Sanger sequencing was performed in 54 HSCR patients to find a pathogenic variant in SEMA3D. Next, we determined SEMA3D expression in 18 HSCR patients and 13 anorectal malformation colons as controls by quantitative real-time polymerase chain reaction (qPCR). Results: No rare variant was found in the SEMA3D gene, except one common variant in exon 17, p.Lys701Gln (rs7800072). The risk allele (C) frequency at rs7800072 among HSCR patients (23%) was similar to those reported for the 1,000 Genomes (27%) and ExAC (28%) East Asian ancestry controls (p = 0.49 and 0.41, respectively). A significant difference in SEMA3D expression was observed between groups (p = 0.04). Furthermore, qPCR revealed that SEMA3D expression was strongly up-regulated (5.5-fold) in the ganglionic colon of HSCR patients compared to control colon (ΔC_T 10.8 ± 2.1 vs. 13.3 ± 3.9; p = 0.025). Conclusions: We report the first study of aberrant SEMA3D expressions in HSCR patients and suggest further understanding into the contribution of aberrant SEMA3D expression in the development of HSCR. In addition, this study is the first comprehensive analysis of SEMA3D variants in the Asian ancestry.

Maternal nutrient intake and fetal gastroschisis: A case-control study

Fetal gastroschisis is a paraumbilical abdominal wall defect with herniation of the abdominal organs. This multifactorial malformation occurs in young pregnant women, and the underlying cause of the disease remains unknown; however, nutritional factors may play a role in its development. This case-control study explored the association of maternal nutrient intake with the occurrence of gastroschisis. The gastroschisis group (GG) comprised 57 pregnant women with fetuses with gastroschisis, and the control group (CG) comprised 114 pregnant women with normal fetuses matched for maternal age, gestational age, and preconception body mass index classification. Nutritional assessments related to the preconception period were obtained using the food consumption frequency questionnaire, and nutrient intakes were calculated using nutrition programs. The median daily calorie intake was higher (2,382.43 vs. 2,198.81; p = .041) in the GG than in the CG. The median intake of methionine (763.89 vs. 906.34; p = .036) and threonine (1,248.34 vs. 1,437.01; p = .018) was lower in the GG than in the CG. Pregnant women with fetuses with gastroschisis have a diet characterized by higher calorie intake and lower levels of essential amino acids (methionine and threonine) during the preconception period than pregnant women with normal fetuses.

Genetic variants conferring susceptibility to gastroschisis: a phenomenon restricted to the interaction with the environment?

BACKGROUND

Genes involved in gastroschisis have shown a strong interaction with environmental factors. However, less is known about its influence. We aimed to systematically review the genetic associations of gastroschisis, to summarize whether its genetic susceptibility has been restricted to the interaction with the environment, and to identify significant gaps that remain for consideration in future studies.

METHODS

Genetic association studies of gastroschisis published 1980-2017 (PubMed/MEDLINE) were independently searched by two reviewers. Significant SNP-gastroschisis associations were grouped into crude and stratified risks, whereas SNPs were assessed from two or more independent studies. Frequencies, odds ratios, and 95% confidence intervals were pooled using descriptive analysis and Chi-square test accounting for heterogeneity.

RESULTS

Seven eligible articles capturing associations of 14 SNPs from 10 genes for crude risk (including 10 and 4 SNPs with increased and decreased risk, respectively) and 30 SNPs from 14 genes for stratified risk in gastroschisis (including 37 and 14 SNPs with increased and decreased risk, respectively) were identified (Fisher's exact test, P = 0.438). The rs4961 (ADD1), rs5443 (GNB3), rs1042713, and rs1042714 (ADRB2) were significantly associated with gastroschisis.

CONCLUSIONS

Genetic susceptibility in gastroschisis is not restricted to the interaction with the environment and should not be too narrowly focused on environmental factors. We found significant associations with four SNPs from three genes related to blood pressure regulation, which supports a significant role of vascular disruption in the pathogenesis of gastroschisis. Future studies considering gene-gene or gene-environmental interactions are warranted for better understanding the etiology of gastroschisis.

Familial occurrence of gastroschisis: a population-based overview on recurrence risk, sex-dependent influence, and geographical distribution

PURPOSE

There is uncertainty over whether familial recurrences in gastroschisis might be higher. Moreover, scant information is available regarding its sociodemographic features. We aim to explore the recurrence risk, sex-dependent influence, and geographical distribution of familial gastroschisis.

METHODS

A systematic review of the literature and data extraction from population-based studies published 1970-2017 (PubMed/MEDLINE) was independently performed by two reviewers. Familial ocurrence of gastroschisis, whereas sociodemographic features from 11 studies were pooled including 862 probands as a base. A descriptive analysis and Chi-square test were performed.

RESULTS

Twenty-four probands had a positive family history of gastroschisis including 49 affected family members, for a recurrence risk of 5.7 and 3% adjusted for proband. Siblings' recurrence was 4.3%. Sex-dependent influence analysis (n = 879, from three studies) evidenced an increased susceptibility to gastroschisis in males (2.5%) compared to females (1.3%) adjusted for proband. Heterogeneity was identified by Fisher's exact test (P = 0.023).

CONCLUSION

Our findings support a greater liability attributable to familial factors on gastroschisis along with significant information for family and prenatal counseling. We suggest that future studies should include for a more accurate account for both familial and environmental confounding factors to uncover relatives and environmental exposures that more limited family histories may have missed.

Maternal Chlamydia infection during pregnancy among younger mothers and risk of gastroschisis in singleton offspring

BACKGROUND

Prevalence of gastroschisis has been increasing in the United States (US) since 1980s. Genital infection with Chlamydia has also been increasing in prevalence, particularly among younger women. The etiology of gastroschisis is unknown. Ongoing research suggests multiple causal factors may be involved, including Chlamydia infection in mothers during pregnancy.

METHODS

Using birth certificate data from 2014 US vital records, we conducted a population-based case-control study to examine the association between prenatal Chlamydia exposure in young women (16-25 years of age) and gastroschisis in singleton offspring. Cases consisted of live births with gastroschisis, and controls had no major birth defects reported in their birth certificate. Logistic regression analysis was used to estimate crude and adjusted odds ratios (cOR and aOR) and 95% confidence intervals (CI).

RESULTS

There were 809 cases (95.6% were isolated cases) and 1,260,293 controls. Chlamydia during pregnancy was reported in 4.5% of case and 3.6% control mothers (p = .21). Case mothers were significantly more likely to be younger (16-20 years of age) at the time of delivery compared to control mothers (p < .0001). We found no significant association between Chlamydia infection during pregnancy and gastroschisis (cOR = 1.24; 95% CI = 0.89-1.73 and aOR = 1.06; 95% CI: 0.66-1.70).

CONCLUSION

With the caveat of possible misclassification of exposure and outcome variables in birth certificate data, we found no significant association between prenatal exposure to Chlamydia and gastroschisis in the offspring born to younger mothers. Future studies should refine measures by focusing on relevant risk period and biomarkers.

Inflammatory breast cancer: High incidence of GCC haplotypes (−1082A/G, −819T/C, and −592A/C) in the interleukin-10 gene promoter correlates with over-expression of interleukin-10 in patients’ carcinoma tissues

Interleukin-10 is involved in carcinogenesis by supporting tumor escape from the immune response. The aim of this study was to assess the single nucleotide polymorphisms, −1082A/G, −819T/C and −592A/C, in interleukin-10 gene promoter in inflammatory breast cancer compared to non–inflammatory breast cancer and association of these polymorphisms with interleukin-10 gene expression. We enrolled 105 breast cancer tissue (72 non–inflammatory breast cancer and 33 inflammatory breast cancer) patients and we determined the three studied single nucleotide polymorphisms in all samples by polymerase chain reaction restriction fragment length polymorphism and investigated their association with the disease and with various prognostic factors. In addition, we assessed the expression of interleukin-10 gene by real-time quantitative reverse transcription polymerase chain reaction and the correlation between studied single nucleotide polymorphisms and interleukin-10 messenger RNA expression. We found co-dominant effect as the best inheritance model (in the three studied single nucleotide polymorphisms in non–inflammatory breast cancer and inflammatory breast cancer samples), and we didn’t identify any association between single nucleotide polymorphisms genotypes and breast cancer prognostic factors. However, GCC haplotype was found highly associated with inflammatory breast cancer risk (p < 0.001, odds ratio = 43.05). Moreover, the expression of interleukin-10 messenger RNA was significantly higher (p < 0.001) by 5.28-fold and 8.95-fold than non–inflammatory breast cancer and healthy control, respectively, where GCC haplotype significantly increased interleukin-10 gene expression (r = 0.9, p < 0.001).

Effects of SEMA3 polymorphisms in Hirschsprung disease patients

PURPOSE

Recently, genetic markers within a locus on 7q21.11 containing the SEMA3A, SEMA3C, and SEMA3D genes were reported to be associated with Hirschsprung disease (HSCR). Here, we investigated three polymorphisms, rs1583147, rs12707682, and rs11766001, at this locus to determine their potential contributions to the susceptibility of Indonesian HSCR patients.

METHODS

Three variants were analyzed in 60 non-syndromic HSCR patients and 118 ethnicity-matched controls for association studies by genotyping.

RESULTS

The risk allele frequencies of SEMA3 rs12707682 (allele C) and rs1583147 (allele T) is higher in cases, 53 and 23 %, than in controls, at 42 and 13 %, respectively. However, these frequency differences were not statistically significant with p value of 0.06 and 0.023, respectively. These findings were consistent with transmission disequilibrium test results with p values of 0.041 and 0.11 for rs12707682 and rs1583147, respectively. Furthermore, the frequencies of SEMA3 rs11766001 risk allele in HSCR cases and controls were 1.7 and 0.8 %, respectively.

CONCLUSIONS

SEMA3 rs12707682 and rs1583147 variants are not common risk factors for HSCR in Indonesia. The rarity of the SEMA3 rs11766001 polymorphism in Indonesian population might be due to a founder effect.