Use of folic acid supplements and risk of cleft lip and palate in infants: a population-based cohort study

Birth defects among offspring of California firefighters, 2007-2019

PURPOSE

Limited research examines birth defects from maternal or paternal firefighting exposure. This study aims to assess if maternal or paternal occupational exposure to firefighting during periconception is associated with offspring birth defects.

METHODS

Data from California birth certificates (2007-2019) were linked to maternal / offspring hospitalization records. Occupation during the periconceptional period was categorized from vital statistics as the following: paternal non-firefighting (n = 4,135,849), paternal firefighting (n = 22,732), maternal non-firefighting (n = 3,332,255) and maternal firefighting (n = 502). Birth defects were identified using ICD codes, grouped by anatomical regions. Adjusted odds ratios were estimated, and sensitivity analyses explored police officer reference groups and detailed birth defect categories.

RESULTS

Offspring of paternal firefighters had lower odds of circulatory defects (aOR = 0.9, 95% CI 0.8, 1.0), oral clefts (aOR = 0.6, 95% CI 0.4, 0.8) and respiratory defects (0.7, 95% CI 0.6, 0.9) compared to paternal non-firefighters. Associations between maternal firefighting and offspring birth defects were imprecise. Substituting police officers as the reference group attenuated findings.

CONCLUSIONS

Offspring of paternal firefighters may have similar or slightly lower birth defect odds compared to offspring of non-firefighters. Limited data was available for assessing maternal firefighting outcomes. Future studies should prioritize studies using occupational exposure matrices to limit misclassification of exposure.

Increased susceptibility for nonsyndromic cleft lip with or without cleft palate by SLC19A1 80G>A genetic variation

BACKGROUND

The disruption of craniofacial developmental pathways during early embryogenesis can lead to conditions such as nonsyndromic cleft lip with or without cleft palate (NSCL/P). Several lines of evidence indicate that inadequate maternal nutrition causes low folate levels during the periconceptional period, resulting in NSCL/P. Although substantial research has been conducted on the possible link between SLC19A1 genetic variants and NSCL/P, the association between SLC19A1 80G>A (rs1051266) and NSCL/P remains unclear. In the present study, the associations of SLC19A1 80G>A with NSCL/P risk were assessed by calculating the pooled odds ratios (ORs) and 95% confidence intervals (CIs) by meta-analyses.

METHODS

Following the PRISMA guidelines, a meta-analysis was conducted on 10 studies assessing the NSCL/P risk associated with SLC19A1 80G>A variant. To ascertain the degree of relationship between the SLC19A1 80G>A genetic variant and the risk of NSCL/P, data were analyzed in allelic, recessive and dominant genetic models. CI of OR for each study and the pooled data were obtained. All statistical analyses were conducted utilizing the MetaGenyo software tool, which integrates the adjustment of P values for multiple testing through the Bonferroni method.

RESULTS

The pooled analysis showed that SLC19A1 80G>A variant significantly increased the NSCL/P risk in the allelic model (OR 1.39; 95% CI 1.00-1.92), recessive model (OR 1.37; 95% CI 1.03-1.82) and dominant models (OR 1.7; 95% CI 1.05-2.90). Publication bias was not observed.

CONCLUSIONS

This study supports that the SLC19A1 80G>A genetic variant is associated with NSCL/P risk.

Disruption of DNA methylation-mediated cranial neural crest proliferation and differentiation causes orofacial clefts in mice

Orofacial clefts of the lip and palate are widely recognized to result from complex gene-environment interactions, but inadequate understanding of environmental risk factors has stymied development of prevention strategies. We interrogated the role of DNA methylation, an environmentally malleable epigenetic mechanism, in orofacial development. Expression of the key DNA methyltransferase enzyme DNMT1 was detected throughout palate morphogenesis in the epithelium and underlying cranial neural crest cell (cNCC) mesenchyme, a highly proliferative multipotent stem cell population that forms orofacial connective tissue. Genetic and pharmacologic manipulations of DNMT activity were then applied to define the tissue- and timing-dependent requirement of DNA methylation in orofacial development. cNCC-specific Dnmt1 inactivation targeting initial palate outgrowth resulted in OFCs, while later targeting during palatal shelf elevation and elongation did not. Conditional Dnmt1 deletion reduced cNCC proliferation and subsequent differentiation trajectory, resulting in attenuated outgrowth of the palatal shelves and altered development of cNCC-derived skeletal elements. Finally, we found that the cellular mechanisms of cleft pathogenesis observed in vivo can be recapitulated by pharmacologically reducing DNA methylation in multipotent cNCCs cultured in vitro. These findings demonstrate that DNA methylation is a crucial epigenetic regulator of cNCC biology, define a critical period of development in which its disruption directly causes OFCs, and provide opportunities to identify environmental influences that contribute to OFC risk.

Prevalence, trend, and associated risk factors for cleft lip with/without cleft palate: a national study on live births from 2016 to 2021

BACKGROUNDS

Cleft lip with or without cleft palate (CL/P) is the most common congenital craniofacial anomaly, including non-syndromic cleft lip with or without cleft palate and cleft palate only. Failure in the fusion of median and lateral nasal processes, the maxillary prominence, and soft tissues around the oral cavity can cause CL/P. Previously, the prevalence has been estimated to be 1 among every 1000 births in 2014 among American neonates and no other reports have been available since. Thus, this study aimed to calculate the prevalence and trend of isolated CL/P among American live births from 2016 to 2021 with its associated risk factors.

METHODS AND MATERIALS

In this cross-sectional population-based retrospective study, we used live birth data provided by the National Center for Health Statistics (NCHS) from the Center for Disease Control and Prevention (CDC). We calculated the prevalence per 10,000 live births of isolated (non-syndromic) CL/P from 2016 to 2021. To examine risk factors for developing isolated CL/P, we used logistic regression modelling.

RESULTS

The total prevalence per 10,000 births from 2016 to 2021 was 4.88 (4.79-4.97), for both sexes, and 5.96 (5.82-6.10) for males, and 3.75 (3.64-3.87) for females. The prevalence did not show any consistent linear decreasing or increasing pattern. We found significant association between increased odds of developing isolated CL/P among cases with 20 to 24 year-old mothers (OR = 1.07, 1.01-1.13, p = 0.013), mothers who smoked 11 to 20 cigarettes per day (OR = 1.46, 1.33-1.60, p <  0.001), mothers with extreme obesity (OR = 1.32, 1.21-1.43, p <  0.001), mothers with grade II obesity (OR = 1.32, 1.23-1.42, p <  0.001), mothers with pre-pregnancy hypertension (OR = 1.17, 1.04-1.31, p = 0.009), mothers with pre-pregnancy diabetes mellitus (OR = 1.96, 1.71-2.25, p <  0.001), and mothers who used assisted reproductive technology (OR = 1.40, 1.18-1.66, p <  0.001).

CONCLUSIONS

Our findings suggest a minuscule increase, albeit insignificant, in the trend of CL/P prevalence from 2016 to 2021. Developing CL/P had greater odds among mothers with pre-pregnancy diabetes, smoking, obesity, and pre-pregnancy hypertension mothers along with mothers who used assisted reproductive technology. Isolated CL/P had the highest prevalence in non-Hispanic Whites, American Indian or Alaskan Native and Native Hawaiian and Other Pacific Islanders.

Characterization of 554 Mexican Patients With Nonsyndromic Cleft Lip and Palate: Descriptive Study

Orofacial clefts are one of the most common birth defects and the most common craniofacial malformation worldwide. The most common orofacial clefts (OFCs) are congenital cleft lip with or without cleft palate (CL ± P) and isolated cleft palate (CP). The incidence of OFCs varies depending on region and ethnicity; however, it affects approximately 1 in 600 newborns worldwide. In most cases, CL ± P and CP are multifactorial congenital malformations, where both exogenous and genetic factors play an important role. The objective of this study was to describe the frequency of potential risk factors associated with the development of CL ± P and CP in Mexican population. Patients were referred for multisystemic treatment, from private and public institutions in different regions of the country (center, north, and south). Sociodemographic information, prenatal and parental history were obtained through direct interviews with the patients or the patients' mothers in the case of underaged patients. Referred patients were invited to participate in the study. No interventions were applied for this study. The relationship between these factors and the prevalence of CL ± P and CP was studied. A total of 554 patients were included, the majority with CLP (30% to 7%), statistically significant differences were found for folic acid ( P = 0.02) consumption. Familial aggregation did not reach statistical significance for first-degree family members ( P = 0.34) but was significant for second-degree family members ( P = 0.007). More risk factors associated with CL ± P and CP may still be unknown, prompting more epidemiological research and research in other little-studied areas, such as; specific genetic factors in Mexican population.

Dietary interventions and nutritional impact on oral health and development: a review

Food and nutrients play a pivotal role in the development of dentition and oral health. While diet includes the overall forms of consumed foods, the nutrients include specific micro- (vitamins and minerals) and macro- (carbohydrates, proteins, and lipids) nutrients. As much as the assimilation of macro and micronutrients depends on proper oral health for ingesting food, oral health, in turn, depends on the availability of nutrients in the food so ingested. Age, certain medical conditions, socioeconomic status, and overall changes in the evolution of society determine the type of diet which in turn influences oral health. This article has touched upon certain salient aspects of these nutrients and their bearing on overall oral health and development.

The relationship between maternal periconceptional micronutrient supplementation and non-syndromic cleft lip/palate in offspring

BACKGROUND

This study aimed to explore the relationship between maternal periconceptional supplementation with folic acid only (FAO) or with multiple micronutrients containing folic acid (MMFA) and non-syndromic cleft lip/palate in offspring.

METHOD

The data came from a prenatal health care system and a birth defects surveillance system in Beijing, China, from 2013 to 2018. Information on maternal FAO/MMFA supplementation was collected by questionnaire in the first trimester, and data on cleft lip/palate were collected at delivery or termination of pregnancy. Inverse probability weighting (IPW) by the propensity score to adjust for the confounders and Poisson regression model was used to estimate risk ratios (RRs) and their 95% confidence intervals (CIs).

RESULTS

A total of 63,969 participants were included in the study. Compared to the no-supplementation group, the adjusted RR for the supplementation group was 0.51 (95% CI: 0.40, 0.64). And the adjusted RRs for FAO and MMFA compared to the no-supplementation group were 0.56 (95% CI: 0.40, 0.76) and 0.48 (95% CI: 0.35, 0.65), respectively. Compared to supplement FAO and MMFA with less than 8 days out of 10 days, the adjusted RRs for FAO and MMFA with 8 or more days out of 10 days were 1.17 (95% CI: 0.78, 1.75), and 2.05 (95% CI: 1.37, 3.31), respectively.

CONCLUSION

Maternal supplementation with micronutrients, either FAO or MMFA, during the periconceptional period can reduce the risk for non-syndromic cleft lip/palate in offspring. However, women should be more cautious with MMFA supplementation.

Genome-wide Interaction Study Implicates VGLL2 and Alcohol Exposure and PRL and Smoking in Orofacial Cleft Risk

Non-syndromic cleft lip with or without cleft palate (NSCL/P) is a common birth defect, affecting approximately 1 in 700 births. NSCL/P has complex etiology including several known genes and environmental factors; however, known genetic risk variants only account for a small fraction of the heritability of NSCL/P. It is commonly suggested that gene-by-environment (G×E) interactions may help explain some of the “missing” heritability of NSCL/P. We conducted a genome-wide G×E interaction study in cases and controls of European ancestry with three common maternal exposures during pregnancy: alcohol, smoking, and vitamin use using a two-stage design. After selecting 127 loci with suggestive 2df tests for gene and G x E effects, 40 loci showed significant G x E effects after correcting for multiple tests. Notable interactions included SNPs of 6q22 near VGLL2 with alcohol and 6p22.3 near PRL with smoking. These interactions could provide new insights into the etiology of CL/P and new opportunities to modify risk through behavioral changes.

The role of smoke from cooking indoors over an open flame and parental smoking on the risk of cleft lip and palate: A case- control study in 7 low-resource countries

Background

Cleft is one of the most common birth defects globally and the lack of access to surgery means millions are living untreated. Smoke exposure from cooking occurs infrequently in developed countries but represents a high-proportion of smoke exposure in less-developed regions. We aimed to study if smoke exposure from cooking is associated with an increased risk in cleft, while accounting for other smoke sources.

Methods

We conducted a population-sampled case-control study of children with cleft lip and/or palate and healthy newborns from Vietnam, Philippines, Honduras, Nicaragua, Morocco, Congo, and Madagascar. Multivariable regression models were used to assess associations between maternal cooking during pregnancy, parental smoking, and household tobacco smoke with cleft.

Results

2137 cases and 2014 controls recruited between 2012-2017 were included. While maternal smoking was uncommon (<1%), 58.3% case and 36.1% control mothers cooked over an open fire inside. Children whose mothers reported cook smoke exposure were 49% (95% confidence interval (CI) = 1.2-1.8) more likely to have a child with a cleft. This was consistent in five of seven countries. No significant associations were found for any other smoke exposure.

Conclusions

Our finding of maternal cook smoke and cleft in low-resource countries, similar to maternal tobacco smoke in high-resource countries, may reflect a common etiology. This relationship was present across geographically diverse countries with variable socioeconomic statuses and access to care. Exposures specific to low-resource settings must be considered to develop public health strategies that address the populations at increased risk of living with cleft and inform the mechanisms leading to cleft development.

Maternal periconceptional folic acid supplementation reduced risks of non-syndromic oral clefts in offspring

Maternal periconceptional folic acid supplementation (FAS) has been documented to be associated with decreased risk of nonsyndromic oral clefts (NsOC). However, the results remain inconclusive. In this population-based case–control study of 807 singletons affected by NsOC and 8070 healthy neonates who were born between October 2010 and September 2015 in Chengdu, China, we examined the association of maternal FAS with the risk of nonsyndromic cleft lip with or without cleft palate (NsCL/P), and cleft palate (NsCP). Unconditional logistic regression analysis was used to estimate the crude and adjusted odds ratios (ORs) and 95% confidential intervals (CI). Significant associations were found between maternal periconceptional FAS and decreased risk of NsCL/P (aOR = 0.41, 95% CI 0.33–0.51). This protective effect was also detected for NsCL (aOR = 0.42, 95% CI 0.30–0.58) and NsCLP (aOR = 0.41, 95% CI 0.31–0.54). Both maternal FAS started before and after the last menstrual period (LMP) were inversely associated with NsCL/P (before LMP, aOR = 0.43, 95% CI 0.33–0.56; after LMP, aOR = 0.41, 95% CI 0.33–0.51). The association between NsCP and maternal FAS initiating before LMP was also found (aOR = 0.52, 95% CI 0.30–0.90). The findings suggest that maternal periconceptional FAS can reduce the risk of each subtype of NsCL/P in offspring, while the potential effect on NsCP needs further investigations.

The use of glutathione to reduce oxidative stress status and its potential for modifying the extracellular matrix organization in cleft lip

OBJECTIVE

Cleft lip (CL) is a common congenital anomaly that can be syndromic or non-syndromic. It can be triggered by the mutation of gene or environmental factors. The incidence of CL is about 1 out of 700 live births. Facial development is a complex process, and there is no existing therapy to prevent the disease development. One of the characteristics in this facial malformation is the increased presence of reactive oxygen species (ROS). In this study, we hypothesize that the antioxidant glutathione (GSH) could help to attenuate the oxidative stress in this disease.

METHODS

Bioinformatics network pharmacology was applied to determine pharmacological targets and molecular mechanisms of GSH treatment for CL. Moreover, RNA-sequencing of the POLR1C knockdown osteoblast CL model was applied to validate the in silico data of using GSH in CL.

RESULTS

Twenty-two core targets of GSH and CL were identified via various bioinformatics tools. The GO and KEGG analysis indicated that GSH could modulate two major families (matrix metalloproteinase and integrins), which are related to extracellular matrix modification and composition for facial development in CL. The findings from POLR1C knockdown model further supported the rescue response of GSH in CL.

CONCLUSIONS

The study uncovered the possible pharmacological mechanism of GSH for treating CL. The data helps research group to focus on the specific pathways for understanding the biological action of GSH for treating the CL in the future.

The association of maternal folic acid supplementation and prenatal folate and vitamin B12 concentrations with child dental development

OBJECTIVE

Low folic acid, folate and vitamin B12 might affect tooth formation and mineralization. The conversion of folic acid into folate is catalysed by the methylenetetrahydrofolate (MTHFR) enzyme which is encoded by the MTHFR gene. Among 3728 mothers and their 10-year-old children from the Generation R Study, we investigated associations of maternal folic acid supplementation and prenatal folate and vitamin B12 concentrations with child dental development. Secondly, we checked the modifying effect of MTHFR-C677T polymorphism.

METHODS

Information on folic acid supplementation was obtained by questionnaires. Concentrations of folate and vitamin B12 were measured from venous samples taken in early pregnancy. Developmental stages of teeth were defined by the Demirjian method at the age-10 assessment. In addition, dental age of the children was calculated using the Dutch standard. GLM and multivariate linear regression models were built to study the associations.

RESULTS

Folic acid supplementation started when pregnancy was known (β = -0.09; 95% CI: -0.17, -0.01) and folic acid supplementation started prior to known pregnancy (β = -0.12; 95% CI: -0.20, -0.04) were both associated with decelerated dental development by 1-2 months lower dental age of 10-year-old children. Folate (β = -0.02, 95% CI: -0.05, 0.02) and vitamin B12 (β = 0.03, 95% CI: -0.00, 0.06) were not associated with dental age. MTHFR-C677T did not modify the associations.

CONCLUSIONS

Maternal folic acid supplementation delays dental development of children by 1-2 months dental age, whereas maternal folate and vitamin B12 concentrations in early pregnancy do not affect the timing of child dental development.

Folate intake, markers of folate status and oral clefts: An updated set of systematic reviews and meta-analyses

BACKGROUND

There has been a longstanding debate about the role of folate in the etiology of orofacial clefts (OFCs). Studies of different measures of nutritional intake or folate status have been done to investigate the possible role of folate in the prevention of OFC. Only one knowledge synthesis has attempted to bring together different types of evidence. The aim of the present work was to update it.

METHODS

Evidence for associations between OFC and dietary folate, supplement use, folic acid fortification, biomarkers of folate status, and variants of MTHFR (C677T and A1298C) were included. Potentially eligible articles were systematically identified from PubMed, Medline, Embase, and Web of Science (2007-2020) and combined using random-effects meta-analysis when appropriate. Quality assessments were conducted using the Newcastle-Ottawa scale and Cochrane's risk of bias tool.

RESULTS

Sixty-four studies published since the previous knowledge synthesis were identified, with eight of these identified through a supplementary search from October, 2018 to August, 2020. There was an inverse association between folic acid-containing supplement use before or during pregnancy and cleft lip with or without cleft palate (CL/P) (OR 0.60, 95% CI 0.51-0.69), with considerable between-study heterogeneity. The prevalence of CL/P showed a small decline post-folic acid fortification in seven studies (OR 0.94, 95% CI 0.86-1.02). No association was found between OFC and genetic markers of folate status. The coronavirus-19 pandemic has threatened food availability globally and therefore there is a need to maintain and even enhance surveillance concerning maternal intake of folate and related vitamins.

CONCLUSIONS

The risk of non-syndromic OFC was reduced among pregnant women with folic acid-containing supplements during the etiologically relevant period. However, high heterogeneity between included studies, incomplete reporting of population characteristics and variation in timing of exposure and supplement types mean that conclusions should be drawn with caution.

Awareness and Use of Folic Acid among Women of Childbearing Age

Folic acid (FA) given before and during pregnancy reduces the risk of several birth defects, including neurologic, cardiac, urinary and other congenital anomalies in the newborn. Several studies around the world showed less than satisfactory awareness and intake of this important vitamin. We undertook the task of exploring this question among Lebanese women of childbearing age.Between June and November 2014, we conducted this cross-sectional study on women aged 20 to 40 years. The subjects, who agreed to participate, completed a questionnaire, which included questions on sociodemographic characteristics, lifestyle, and knowledge about FA roles during pregnancy, as well as their babies' health.Seventy-six percent reported having knowledge about FA during pregnancy, but only a small proportion knew the benefits for taking it. Also, 93.9% of women took FA supplements during pregnancy, however only 33.6% of the participants took FA before becoming aware of their pregnancy.Public health interventions to improve awareness of FA's roles before and during pregnancy are crucial to curtail birth defects. It is our opinion that it is a very fruitful preventive medicine tool in which every community should invest.

Maternal folic acid supplementation reduces the severity of cleft palate in Tgf-β3 null mutant mice

BACKGROUND

Cleft palate (CP) constitutes the most frequently seen orofacial cleft and is often associated with low folate status. Folate plays an essential role in the human body as a major coenzyme in one-carbon metabolism, including DNA synthesis, repair, and methylation. Whether the administration of isolated folic acid (FA) supplements prevents the CP caused by genetic mutations is unknown, as is its effect on the mechanisms leading to palate fusion.

METHODS

FA was administered to females from two different strains of transforming growth factor β₃ heterozygous mice. Null mutant progeny of these mice exhibit CP in 100% of cases of varying severity. We measured cleft length, height of palatal shelf adhesion, and the number of proliferating mesenchymal cells. Immunohistochemistry was also carried for collagen IV, laminin, fibronectin, cytokeratin-17, and EGF.

RESULTS

FA supplementation significantly reduced CP severity and improved palatal shelf adhesion in both strains both in vivo and in vitro. Medial edge epithelium proliferation increased, and its differentiation was normalized as indicated by the presence and disposition of collagen IV, laminin, fibronectin, and cytokeratin-17.

CONCLUSIONS

A maternal FA supplementation reduces the CP appearance by improving the mechanisms leading to palatal shelf adhesion.

Folate supplementation to prevent birth abnormalities: evaluating a community-based participatory action plan for refugees and migrant workers on the Thailand-Myanmar border

Objectives

Preconception folic acid (PFA) taken at least 3 months before conception can decrease the incidence of neural tube defects (NTDs) by approximately 46%. NTDs contribute significantly to neonatal morbidity and mortality in migrant and refugee populations on the Thailand-Myanmar border (incidence 1.57/1000 live births). This audit aimed to assess uptake of PFA among migrant and refugee women, evaluate knowledge about PFA among local healthcare workers and implement a participatory community intervention to increase PFA uptake and decrease NTD incidence in this population.

Study design

A mixed-methods baseline evaluation was followed by an intervention involving health worker education and a community outreach program. A follow-up audit was performed 18 months post-intervention.

Methods

Data were gathered via surveys, short interviews and focus group discussions. The intervention program included community-based workshops, production and distribution of printed flyers and posters, and outreach to various local organisations.

Results

Uptake of PFA was <2% both before and after the intervention. Despite a substantial increase in local healthcare worker knowledge of PFA, no significant improvement in PFA uptake after the intervention was detected. Most pregnancies in this local community sample were reported to be unplanned.

Conclusions

High rates of NTDs with low PFA uptake remains a major public health challenge in this transient population. Results indicate that improved health worker knowledge alone is not sufficient to enhance PFA uptake in this population. Integration of PFA education within expanded family planning programs and broad-based food fortification may be more effective.

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Audited preconception folic acid (PFA) campaign on Thai-Myanmar border.

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Low awareness of PFA among health workers and migrant/refugee pregnant women.

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Improved local health worker PFA knowledge after campaign and follow-up held after 18 months.

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Overall, campaign proved ineffective in increasing PFA uptake among pregnant women.

Proportion of Orofacial Clefts Attributable to Recognized Risk Factors

OBJECTIVE

Estimate the population attributable fraction (PAF) for a set of recognized risk factors for orofacial clefts.

DESIGN

We used data from the National Birth Defects Prevention Study. For recognized risk factors for which data were available, we estimated crude population attributable fractions (cPAFs) to account for potential confounding, average-adjusted population attributable fractions (aaPAFs). We assessed 11 modifiable and 3 nonmodifiable parental/maternal risk factors. The aaPAF for individual risk factors and the total aaPAF for the set of risk factors were calculated using a method described by Eide and Geffler.

SETTING

Population-based case-control study in 10 US states.

PARTICIPANTS

Two thousand seven hundred seventy-nine cases with isolated cleft lip with or without cleft palate (CL±P), 1310 cases with isolated cleft palate (CP), and 11 692 controls with estimated dates of delivery between October 1, 1997, and December 31, 2011.

MAIN OUTCOME MEASURES

Crude population attributable fraction and aaPAF.

RESULTS

The proportion of CL±P and CP cases attributable to the full set of examined risk factors was 50% and 43%, respectively. The modifiable factor with the largest aaPAF was smoking during the month before pregnancy or the first month of pregnancy (4.0% for CL±P and 3.4% for CP). Among nonmodifiable factors, the factor with the largest aaPAF for CL±P was male sex (27%) and for CP it was female sex (16%).

CONCLUSIONS

Our results may inform research and prevention efforts. A large proportion of orofacial cleft risk is attributable to nonmodifiable factors; it is important to better understand the mechanisms involved for these factors.

Evidence of interaction between genes in the folate/homocysteine metabolic pathway in controlling risk of non-syndromic oral cleft

OBJECTIVE

Little consistent evidence is available for the association between the risk of non-syndromic cleft lip with or without cleft palate (NSCL/P) and any of the individual genes in the folate/homocysteine metabolic pathway. We investigated the genes in the folate pathway to further clarify its potential influence on the risk of NSCL/P considering gene-gene (G×G) interaction.

SUBJECTS AND METHODS

We selected markers in 18 genes from the pathway and applied Cordell's method to test for G×G interaction using 1,908 NSCL/P case-parent trios ascertained in an international consortium where a genomewide association study (GWAS) of oral clefts was conducted.

RESULTS

We found intriguing signals among Asian and European ancestry groups for G×G interaction between markers in betaine-homocysteine methyltransferase gene (BHMT/BHMT2) and dimethylglycine dehydrogenase gene (DMGDH) attaining genomewide significance. In the pooled data, the top significant interaction was found between rs13158309 (BHMT) and rs10514154 (DMGDH, p = 1.45 × 10^-12 ).

CONCLUSIONS

Our study illustrated the importance of taking into account potential G×G interaction for genetic association analysis in NSCL/P, and this study suggested both BHMT/BHMT2 and DMGDH should be considered as candidate genes for NSCL/P in future studies.

Tongue Abnormalities Are Associated to a Maternal Folic Acid Deficient Diet in Mice

It is widely accepted that maternal folic acid (FA) deficiency during pregnancy is a risk factor for abnormal development. The tongue, with multiple genes working together in a coordinated cascade in time and place, has emerged as a target organ for testing the effect of FA during development. A FA-deficient (FAD) diet was administered to eight-week-old C57/BL/6J mouse females for 2–16 weeks. Pregnant dams were sacrificed at gestational day 17 (E17). The tongues and heads of 15 control and 210 experimental fetuses were studied. In the tongues, the maximum width, base width, height and area were compared with width, height and area of the head. All measurements decreased from 10% to 38% with increasing number of weeks on maternal FAD diet. Decreased head and tongue areas showed a harmonic reduction (Spearman nonparametric correlation, Rho = 0.802) with respect to weeks on a maternal FAD diet. Tongue congenital abnormalities showed a 10.9% prevalence, divided in aglossia (3.3%) and microglossia (7.6%), always accompanied by agnathia (5.6%) or micrognathia (5.2%). This is the first time that tongue alterations have been related experimentally to maternal FAD diet in mice. We propose that the tongue should be included in the list of FA-sensitive birth defect organs due to its relevance in several key food and nutrition processes.

Folic acid supplement use and the risk of gestational hypertension and preeclampsia

BACKGROUND

Hypertensive disorders of pregnancy are among the leading causes of maternal morbidity and mortality. Studies suggest that the use of folic acid may lower the risk of hypertensive disorders in pregnant women.

AIM

The aim of this study was to assess the effects of timing and duration of folic acid-containing supplement use on the risk for gestational hypertension and preeclampsia.

METHODS

Exposures and outcomes data were obtained through interviews and review of participant's medical records from the MotherToBaby cohort studies across the United States and Canada. Demographics, medical history, lifestyle factors, substance use, and fetal sex were assessed as potential confounders. Unadjusted and adjusted risks for gestational hypertension and preeclampsia were examined using odds ratios and 95% confidence intervals.

FINDINGS

3247 women were included in the study. Compared to non-supplement use, early and late supplement use were not significantly associated with the development of gestational hypertension or preeclampsia. The odds of developing gestational hypertension and preeclampsia were significantly reduced as the duration of folic acid-containing supplement use increased.

CONCLUSION

Findings from this study suggest that the use of folic acid-containing supplements may mitigate the risk for gestational hypertension and preeclampsia.

Associations between the NOGGIN rs227731 polymorphism and NSCL/P risk may be associated with ethnicities: A meta-analysis

BACKGROUND

The aim of this study was to evaluate the association between the noggin rs227731 polymorphism on chromosome 17q22 and risk of nonsyndromic cleft lip with or without palate (NSCL/P).

METHODS

Three online databases were searched, including Embase, PubMed, and Chinese National Knowledge Infrastructure. The strength of the associations was evaluated by odds ratios (ORs) and 95% confidence intervals (CIs). We also made a subgroup analysis to explore sources of heterogeneity.

RESULTS

Nine comparisons from seven studies were included in this meta-analysis. We used five genetic models and found that the noggin rs227731 polymorphism may increase NSCL/P risk in Caucasians: C versus A: OR = 1.43, 95% CI, 1.30-1.58; CC versus AA: OR = 2.00, 95% CI, 1.59-2.52; CA versus AA: OR = 1.50, 95% CI, 1.27-1.77; CC+CA versus AA: OR = 1.64, 95% CI, 1.40-1.92; CC versus CA+AA: OR = 1.56, 95% CI, 1.30-1.87. However, for the Chinese population, no significant association between the rs227731 polymorphism and NSCL/P risk was found: C vs. A: OR = 1.04, 95% CI, 0.81-1.33; CC vs. AA: OR = 1.01, 95% CI, 0.52-1.95; CA vs. AA: OR = 1.03, 95% CI, 0.75-1.40; CC+CA vs. AA: OR = 1.04, 95% CI, 0.76-1.43; CC vs. CA+AA: OR = 1.01, 95% CI, 0.56-1.81.

CONCLUSION

Our meta-analysis suggested that the rs227731 polymorphism may increase NSCL/P risk in Caucasians and may have no significant association in the Chinese population. Effects of individual and environmental risk factors and of gene-environment interactions may play a different role in Caucasians than in the Chinese population. More relevant case-control studies are required to obtain more precise results. Birth Defects Research 109:445-451, 2017. © 2017 Wiley Periodicals, Inc.

A discriminant analysis prediction model of non-syndromic cleft lip with or without cleft palate based on risk factors

BACKGROUND

A risk prediction model of non-syndromic cleft lip with or without cleft palate (NSCL/P) was established by a discriminant analysis to predict the individual risk of NSCL/P in pregnant women.

METHODS

A hospital-based case-control study was conducted with 113 cases of NSCL/P and 226 controls without NSCL/P. The cases and the controls were obtained from 52 birth defects' surveillance hospitals in Hunan Province, China. A questionnaire was administered in person to collect the variables relevant to NSCL/P by face to face interviews. Logistic regression models were used to analyze the influencing factors of NSCL/P, and a stepwise Fisher discriminant analysis was subsequently used to construct the prediction model.

RESULTS

In the univariate analysis, 13 influencing factors were related to NSCL/P, of which the following 8 influencing factors as predictors determined the discriminant prediction model: family income, maternal occupational hazards exposure, premarital medical examination, housing renovation, milk/soymilk intake in the first trimester of pregnancy, paternal occupational hazards exposure, paternal strong tea drinking, and family history of NSCL/P. The model had statistical significance (lambda = 0.772, chi-square = 86.044, df = 8, P < 0.001). Self-verification showed that 83.8 % of the participants were correctly predicted to be NSCL/P cases or controls with a sensitivity of 74.3 % and a specificity of 88.5 %. The area under the receiver operating characteristic curve (AUC) was 0.846.

CONCLUSIONS

The prediction model that was established using the risk factors of NSCL/P can be useful for predicting the risk of NSCL/P. Further research is needed to improve the model, and confirm the validity and reliability of the model.

Association between IRF6 and 8q24 polymorphisms and nonsyndromic cleft lip with or without cleft palate: Systematic review and meta-analysis

BACKGROUND

We conducted a systematic review and meta-analysis of interferon regulatory factor 6 and 8q24 polymorphisms with nonsyndromic cleft lip with/without cleft palate (NSCL/P).

METHODS

Data extraction was independently performed by two reviewers. Genotypic effects of four polymorphisms from 31 studies were pooled separately by ethnicity using a mixed-effect logit model with accounting for heterogeneity.

RESULTS

For rs2235371, AA and GA carried, respectively, 51% (95% confidence interval [CI], 37%-61%) and 42% (95% CI, 32%-50%) lower risks of NSCL/P than GG genotypes in Asians, but these genotypes were not significant in Caucasians. For rs2013162, only AA was significant, that is, carried 0.65 (95% CI, 0.52-0.82) times lower odds than CC in Caucasians but not for Asians. For rs642961, AA and GA genotypes, respectively, carried 2.47 (95% CI, 1.41-4.35) and 1.40 (95% CI, 1.12-1.75) times higher odds in Asian, and 2.03 (95% CI, 1.52-2.71) and 1.58 (95% CI, 1.37-1.82) times higher odds in Caucasians compare with GG genotypes. For rs987525, AA and CA genotypes carried 2.27 (95% CI, 1.43-3.60) and 1.34 (95% CI, 1.02-1.77) times higher odds in Asian, and 5.25 (95% CI, 3.98-6.91) and 2.13 (95% CI-1.82, 2.49) times higher odds in Caucasians, and 1.42 (95% CI, 1.10-1.82) and 1.28 (95% CI, 1.09-1.50) times higher odds in mixed ethnicities compared with CC genotypes. These variant effects remained significant based on applying Bonferroni corrected-thresholds, except in the mixed ethnicity.

CONCLUSION

We show robust variant effects in NSCL/P. Considering them with other genes and risk factors might be useful to improve prediction of NSCL/P occurrence. Birth Defects Research (Part A) 106:773-788, 2016. © 2016 The Authors Birth Defects Research Part A: Clinical and Molecular Teratology Published by Wiley Periodicals, Inc.

[Neural tube defects and folic acid: a historical overview of a highly successful preventive intervention]

This article gives a broad overview of part of the historical evolution of medical knowledge about neural tube defects (NTD) and the discovery of vitamin B9 or folic acid, as well as some relevant research events that, over the course of several centuries, defined the relationships between the understanding of central nervous system embryology, the discovery of the vitamin, the correlation between folic acid and cell proliferation and lastly the development of preventive measures for this type of defects. This narrative allows us to examine historically relevant concepts underlying clinical actions with a populational impact that prevent NTDs via folic acid consumption prior to conception.

Cleft lip and palate and related factors: A 10 years study in university hospitalised patients at Mashhad--Iran

BACKGROUND

Oral-facial clefts including cleft lip and palate are the most common congenital malformations of the head and neck. Environmental factors such as maternal hormonal disorders, use of psychiatric medications, vitamin and folic acid deficiency, hypoxia, cigarette smoking and maternal obesity and overweight can affect the incidence of these disorders. In Iran, one of the associated problems is a lack of accurate statistics regarding the present status of the patients, which can cause a disturbance in the health programmes of Ministry of Health and Medical Education. The aim of this study was to report the status of 398 cases of cleft lip and palate in Sheikh and Imam Reza Hospitals of Mashhad over a 10-year period.

MATERIALS AND METHODS

This retrospective descriptive study was performed using data collection method and included the evaluation of the recorded files and completing the data forms. In this study, the file records of 398 patients referring to Mashhad Sheikh and Imam Reza (P.U.H) Hospitals were studied, from the beginning of 2002 to the end of 2011; the obtained data from the files were collected and classified.

RESULTS

The highest frequency was related to cleft palate alone (40.7%); frequencies were lower regarding the cleft lip and palate and cleft lip alone (34.41% and 24.87%, respectively). Approximately, half of the patients were from rural areas of the city and had articulation disorders. Most of the patients were the first-born children of the family and their parents were consanguineously married; about one-third of the patients had a family history of the disease.

CONCLUSION

According to the results of the present study, cleft lip is more frequent in males and cleft palate is more prevalent in females; the obtained results are consistent with the global statistics.

The impact of obstetric mode of delivery on childhood behavior

PURPOSE

We investigated the hypothesis that mode of delivery affects childhood behavior and motor development and examined whether there are sex-specific associations, i.e., whether males and females have different risk estimates.

METHODS

Families with infants born between December 2007 and May 2008 (N = 11,134) were randomly selected and recruited to the Growing Up in Ireland study. Mode of delivery was classified into spontaneous vaginal delivery; instrumental vaginal delivery; emergency Cesarean section (CS); and elective CS. The 'Ages and Stages Questionnaire' was completed at age 9-months and the 'Strengths and Difficulties Questionnaire' at 3 years. Data were weighted to represent the national sample (N = 73,662) and multivariate logistic regression was used for the statistical analyses.

RESULTS

At age 9 months, elective CS was associated with a delay in personal social skills [adjusted odds ratio, aOR 1.24; (95% confidence interval, CI 1.04, 1.48)] and gross motor function [aOR 1.62, (95% CI 1.34, 1.96)], whereas emergency CS was associated with delayed gross motor function [aOR 1.30, (95% CI 1.06, 1.59)]. At age 3 years there was no significantly increased risk of an abnormal total SDQ score across all modes of delivery.

CONCLUSIONS

Children born by elective CS may face a delay in cognitive and motor development at age 9 months. No increase in total SDQ score was found across all modes of delivery. Further investigation is needed to replicate these findings in other populations and explore the potential biological mechanisms.

Folic acid supplements and risk for oral clefts in the newborn: a population-based study

Results from previous studies on maternal folic acid intake and infant oral clefts are inconclusive. The aim of the present study was to investigate the association between women’s use of folic acid and/or multivitamin supplements and the risk for oral cleft in the newborn. We used data from the Medical Birth Registry of Norway based on all births in Norway from 1999 to 2013. A total of 528 220 women had 880 568 pregnancies, resulting in 896 674 live births and stillbirths, of which 1623 had oral clefts (isolated oral clefts, n 1311; non-isolated oral clefts, n 312). Altogether, 21·5 % of women were vitamin supplement users before pregnancy. The birth prevalence of oral clefts was 1·81/1000 live births and stillbirths. Relative risks (RR) were estimated with log-binomial regression. For pregnancies with maternal use of vitamins, the adjusted RR for clefts overall was 0·90 (95 % CI 0·79, 1·04). The adjusted RR for cleft palate only (n 586) was 0·84 (95 % CI 0·66, 1·06) and that for cleft lip with or without cleft palate (n 1037) was 0·94 (95 % CI 0·79, 1·13). Associations were stronger for cleft cases that occurred in combination with other malformations (adjusted RR 0·63; 95 % CI 0·45, 0·88), although vitamin supplements provided no protection against isolated clefts (adjusted RR 0·98; 95 % CI 0·84, 1·15). In conclusion, our study demonstrates no statistically significant association between vitamin use and isolated oral clefts. However, we found lower risk for oral clefts that occurred in combination with other malformations.

Newborn craniofacial malformations: orofacial clefting and craniosynostosis

Craniofacial malformations are among the most common birth defects. Although most cases of orofacial clefting and craniosynostosis are isolated and sporadic, these abnormalities are associated with a wide range of genetic syndromes, and making the appropriate diagnosis can guide management and counseling. Patients with craniofacial malformation are best cared for in a multidisciplinary clinic that can coordinate the care delivered by a diverse team of providers.

MTHFD1 gene polymorphisms as risk factors involved in orofacial cleft: an independent case-control study and a meta-analysis

BACKGROUND

Orofacial clefts (OFCs) were among the most familiar birth defects in the world, which had been reported to be influenced by the folic acid ingestion in pregnancy previously. Methylenetetrahydrofolate dehydrogenase1 (MTHFD1) gene was associated with the susceptibility of OFCs through a complex metabolism correlate with folic acid. The aim of our study was to evaluate the correlation of five single-nucleotide polymorphisms (SNPs) within MTHFD1 related to the OFCs risk in a Chinese population.

METHODS

By the use of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), we genotyped 5 filtered SNPs (identified by Haploview 4.2 software with HapMap databases) on MTHFD1 gene: 118913T>C, 31136A>G, 58893A>G, 1958G>A and 61869T>C of 216 subjects (108 OFCs cases and 108 healthy controls) from a Chinese population. The association between these SNPs and OFCs risk was investigated by student t-test, one-way analysis of variance (ANOVA) and chi-square test with GraphPad Prism 5.0 software. Furthermore, we also performed a meta-analysis of relevant studies to investigate the association between MTHFD1 1958G>A and the susceptibility of OFCs.

RESULTS

Through the genotyping, the AA genotype was found significantly correlated with the susceptibility of OFCs compared with other SNPs on MTHFD1, yielding an OR of 2.71 (95% CI = 1.12-6.58, P = 0.025) under the homozygous model and an OR of 2.37 (95% CI = 1.06-5.30, P = 0.033) under the recessive model. While other selected SNPs 118913T>C and 31136A>G were also associated with an increased OFC risk, the results were not statistically significant (all P > 0.05). However, the overall result of meta-analysis did not support the conclusion that the 1958G>A variant could be a genetic susceptible factor for OFCs (A allele vs. G allele: OR = 1.02, 95% CI = 0.85-1.23, AA vs. GG: OR = 1.06, 95% CI = 0.69-1.63, GA vs. GG: OR = 1.02, 95% CI = 0.81-1.27, AA vs. GG+GA: OR = 0.94, 95% CI = 0.61-1.46, AA+GA vs. GG: OR = 0.94, 95% CI = 0.74-1.19).

CONCLUSIONS

The MTHFD1 1958G>A variant was significantly associated with the increased OFCs risk in Chinese population. However, this association was not supported by meta-analysis of all relevant studies. Further investigations about functional impact of this polymorphism were needed.

Folate and folic acid in the periconceptional period: recommendations from official health organizations in thirty-six countries worldwide and WHO

Objective

To summarize the recommendations on folate intake and folic acid supplementation and fortification in the periconceptional period, aimed at prevention of neural tube defects (NTD), provided by official health organizations in different countries worldwide and WHO.

Design

Information on recommendations for folate and folic acid intake in the periconceptional period was gathered from the websites of official national health organizations of several countries worldwide and from the WHO website.

Setting

WHO, selected developed countries and emerging economies, totalling thirty-six countries worldwide (some European, BRICS, G8, Asian Tiger/Asian Dragon and Australia).

Results

Recommendations differ between countries, although the majority (69·4 %) recommend a healthy diet plus a folic acid supplement of 400 µg/d from preconception (4–12 weeks) until the end of the first trimester of pregnancy (8–12 weeks). The same recommendation is issued by the WHO. Dosages for women at high risk of NTD are up to 4–5 mg/d (for 41·7 % of studied countries). The recommended intake for folate is in the range of 300–400 µg/d for women of childbearing age and 500–600 µg/d for pregnant women in different countries and WHO. Five countries emphasize the importance of a healthy diet rendering supplementation needless. By contrast, five others advise a healthy diet and supplementation plus mandatory fortification. Only one mentions the importance of ensuring an adequate folate status and refers to checking with a health-care provider on the need for supplements.

Conclusions

Different recommendations regarding folate and folic acid, seeking NTD prevention, are available worldwide; however, most countries and WHO focus on a healthy diet and folic acid supplementation of 400 µg/d periconceptionally.

Risk factors involved in orofacial cleft predisposition - review

Clefts that occur in children are a special topic. Avoiding risk factors, and also an early diagnosis of cleft possibility can result in minimizing or avoiding them. If on the other hand when clefts occur they require a long-term, multistage specialized treatment. Etiology of clefts seems to be related to many factors. Factors such as genetic, environmental, geographic and even race factors are important. Identification of risk factors can lead to prevention and prophylactic behaviors in order to minimize its occurrence. Exposure to environmental factors at home and work that lead to cleft predisposition should not be disregarded. It seems that before planning a family it would be wise to consult with doctors of different specializations, especially in high-risk families with cleft history in order to analyze previous lifestyle. Clefts are very common in hereditary facial malformations and are causing a lot of other irregularities in the head and neck region. In this paper after a brief papers review authors present socio-geographic, environmental and also work place related factors that are influencing pregnant women condition and should be taken under serious consideration.

Maternal Supplementary Folate Intake, Methylenetetrahydrofolate Reductase (MTHFR) C677T and A1298C Polymorphisms and the Risk of Orofacial Cleft in Iranian Children

BACKGROUND

The purpose of this study was to describe the association of MTHFR gene single nucleotide polymorphisms (C677T and A1298C) and maternal supplementary folate intake with orofacial clefts in the Iranian population.

METHODS

In this case-control study, peripheral venous blood was taken from 65 patients with orofacial clefts and 215 unaffected controls for DNA extraction and kept in EDTA for further analysis. The genotyping was carried out using Polymerase Chain Reaction (PCR) followed by Restriction Fragment Length Polymorphism (RFLP) and gel electrophoresis. Data were analyzed using Chi square test and logistic regression tests.

RESULTS

Genotype frequencies of 677TT were reported to be 13.5 and 36.1% in controls and CL/P patients, respectively, which showed a significant difference compared to CC as reference (OR=4.118; 95% CI=1.997-8.492; p=0.001). Conversely, 1298CC with frequencies of 10.8 and 12.7% in controls and patients, respectively, showed no significant difference compared to AA (OR=2.359; 95% CI=0.792-7.023; p=0.123). Comparing patients whose mothers did not report the folate supplement intake during pregnancy, to controls, it was observed that lack of folate intake was a predisposing factor for having a child with oral clefts (OR=5/718, p=0.000).

CONCLUSION

Children carrying the 677TT variant of the MTHFR gene may have an increased risk of CL/P. In addition, the finding that the risk associated with this allele was obviously higher when the mothers didn't use folic acid, supports the hypothesis that folic acid may play a role in the etiology of CL/P.

Classification, epidemiology, and genetics of orofacial clefts

Orofacial clefts (OFCs) include a broad range of facial conditions that differ in cause and disease burden. In the published literature, there is substantial ambiguity in both terminology and classification of OFCs. This article discusses the terminology and classification of OFCs and the epidemiology of OFCs. Demographic, environmental, and genetic risk factors for OFCs are described, including suggestions for family counseling. This article enables clinicians to counsel families regarding the occurrence and recurrence of OFCs. Although much of the information is detailed, it is intended to be accessible to all health professionals for use in their clinical practices.

Folic acid supplementation in pregnancy and implications in health and disease

Maternal exposure to dietary factors during pregnancy can influence embryonic development and may modulate the phenotype of offspring through epigenetic programming. Folate is critical for nucleotide synthesis, and preconceptional intake of dietary folic acid (FA) is credited with reduced incidences of neural tube defects in infants. While fortification of grains with FA resulted in a positive public-health outcome, concern has been raised for the need for further investigation of unintended consequences and potential health hazards arising from excessive FA intakes, especially following reports that FA may exert epigenetic effects. The objective of this article is to discuss the role of FA in human health and to review the benefits, concerns and epigenetic effects of maternal FA on the basis of recent findings that are important to design future studies.

Influence of the 20-week anomaly scan on prenatal diagnosis and management of fetal facial clefts

OBJECTIVE

To investigate trends in prenatal diagnosis and termination of pregnancy rates in cases of fetal cleft lip with or without cleft palate (CL ± P), before and after the introduction in The Netherlands of the 20-week anomaly scan in 2007, and to assess the accuracy of this scan for the diagnosis of facial clefts.

METHODS

This was a retrospective cohort study of consecutive cases of CL ± P diagnosed in 2001-2010 in the referral region of the Academic Medical Centre. Cases diagnosed prenatally were identified from the hospital's database. These data, grouped according to the periods before and after the introduction of the routine 20-week anomaly scan, were compared with data of all cases managed by the multidisciplinary cleft team, which services the same region, to identify cases of CL ± P that were not seen prenatally.

RESULTS

We identified 123 cases of CL ± P diagnosed prenatally, of which 76% (93/123) were diagnosed before 24 weeks. In one case, the CL ± P was not confirmed after birth. There were 46 cases with associated structural anomalies and 76 isolated cases. The median gestational age at diagnosis decreased by 2 weeks after 2007 (P = 0.02). The proportion of isolated clefts detected prenatally increased significantly after 2007 (P < 0.0001), whereas the proportion of associated clefts remained stable over the years (P = 0.426). The overall detection rate of CL ± P increased from 43% before 2007 to 86% after 2007 (P < 0.0001), without an increase in terminations of pregnancy.

CONCLUSION

Introduction of the routine fetal anomaly scan has decreased the gestational age at diagnosis of CL ± P and has increased the proportion diagnosed prenatally, without a significant change in the number of terminations of pregnancy.

A case-control study of environmental exposures for nonsyndromic cleft of the lip and/or palate in eastern Guangdong, China

OBJECTIVE

To study the relationship between environmental factors and nonsyndromic cleft of the lip and/or palate (NSCLP) in eastern Guangdong for the prevention of NSCLP.

METHODS

A 1:1 retrospective case-control study was carried out. Data from 479 children with NSCLP who accepted comprehensive care in our center were recruited as cases from April 2010 to April 2013. An equal number of controls were recruited from pediatrics during the same period. Then we conducted face-to-face interviews with both parents using a structural questionnaire to identify the relationship between NSCLP and environmental risk factors.

RESULTS

Univariate Chi-square analysis identified 23 factors (P<0.05) as being significantly related to NSCLP. Stepwise multiple logistic regression analyses demonstrated that there were 16 factors significantly associated with this disease. Being male (OR=0.609), parental childbearing age of 25-29 years (ORfather=0.633; ORmother=0.469), higher parental education level (high school or greater) and folic acid supplementation (OR=0.360) were protective factors against NSCLP. However, positive family history of NSCLP (OR=54.132), positive maternal abortion history (OR=3.698), high or low parental age at time of childbirth, poor maternal education level (primary school) (OR=2.258), maternal common cold during pregnancy (OR=1.464), and drug use during pregnancy (OR=3.364) were significant risk factors for NSCLP.

CONCLUSION

The findings are beneficial for researchers to understand the etiology of NSCLP and to lay a solid foundation for the prevention of NSCLP in eastern Guangdong through educational programs to teach parents about the benefits of folic acid supplementation, adequate parental age at childbirth (25-29 years), higher parental education level (high school or higher), and the dangers of common cold and drug use during the first trimester of pregnancy, positive family history and maternal abortion history.

Cleft lip - a comprehensive review

Orofacial clefts comprise a range of congenital deformities and are the most common head and neck congenital malformation. Clefting has significant psychological and socio- economic effects on patient quality of life and require a multidisciplinary team approach for management. The complex interplay between genetic and environmental factors play a significant role in the incidence and cause of clefting. In this review, the embryology, classification, epidemiology, and etiology of cleft lip are discussed. The primary goals of surgical repair are to restore normal function, speech development, and facial esthetics. Different techniques are employed based on surgeon expertise and the unique patient presentations. Pre-surgical orthopedics are frequently employed prior to definitive repair to improve outcomes. Long term follow up and quality of life studies are discussed.

MTHFR rs2274976 polymorphism is a risk marker for nonsyndromic cleft lip with or without cleft palate in the Brazilian population

BACKGROUND

Polymorphisms within the MTHFR (rs2274976) and MTHFD1 (rs2236225) genes were previously associated with maternal susceptibility for having an offspring with nonsyndromic cleft lip with or without cleft palate (NSCL/P) in the Brazilian population. However, as the genotypes of the patients with NSCL/P were not evaluated, it is not clear whether the effects are associated with maternal or offspring genotypes. The aim of this study was to evaluate the association of rs2274976 and rs2236225 in the pathogenesis of NSCL/P.

METHODS

By using the TaqMan 5'-exonuclease allelic discrimination assay, the present study genotyped the rs2274976 and rs2236225 polymorphisms in 147 case-parent trios, 181 isolated samples of NSCL/P and 478 healthy controls of the Brazilian population. Transmission disequilibrium test and structured case-control analysis based on the individual ancestry proportions were performed.

RESULTS

The transmission disequilibrium test showed a significant overtransmission of the rs2274976 A allele (p = 0.004), but no preferential parent-of-origin transmission was detected. The structured case-control analysis supported those findings, revealing that the minor A allele of rs2274976 was significantly more frequent in NSCL/P group compared with control group (p = 0.001), yielding an odds ratio of 3.46 (95% confidence interval, 2.05-5.85). No association of rs2236225 polymorphism with NSCL/P was observed in both transmission disequilibrium test and case-control analysis.

CONCLUSION

The results of the study revealed that the presence of the rs2274976 A allele is a risk marker for the development of NSCL/P in the Brazilian population.

Periconceptional folic acid associated with an increased risk of oral clefts relative to non-folate related malformations in the Northern Netherlands: a population based case-control study

Periconceptional folic acid has been associated with a reduced risk of neural tube defects, but findings on its effect in oral clefts are largely inconclusive. This case-control study assesses the effects of periconceptional folic acid on cleft risk, using complementary data from the Dutch Oral Cleft Registry and a population-based birth defects registry (Eurocat) of children and foetuses born in the Northern Netherlands between 1997 and 2009. Cases were live-born infants with non-syndromic clefts (n = 367) and controls were infants or foetuses with chromosomal/syndromal (n = 924) or non-folate related anomalies (n = 2,021). We analyzed type/timing/duration of supplement use related to traditional cleft categories as well as to their timing (early/late embryonic periods) and underlying embryological processes (fusion/differentiation defects). Consistent supplement use during the aetiologically relevant period (weeks 0-12 postconception) was associated with an increased risk of clefts (adjusted odds ratio 1.72, 95% confidence interval 1.19-2.49), especially of cleft lip/alveolus (3.16, 1.69-5.91). Further analysis systematically showed twofold to threefold increased risks for late differentiation defects-mainly clefts of the lip/alveolus-with no significant associations for early/late fusion defects. Effects were attributable to folic acid and not to other multivitamin components, and inclusion of partial use (not covering the complete aetiologically relevant period) generally weakened associations. In conclusion, this study presents several lines of evidence indicating that periconceptional folic acid in the Northern Netherlands is associated with an increased risk of clefts, in particular of cleft lip/alveolus. This association is strengthened by the specificity, consistency, systematic pattern, and duration of exposure-response relationship of our findings, underlining the need to evaluate public health strategies regarding folic acid and to further investigate potential adverse effects.

Elevated dimethylglycine in blood of children with congenital heart defects and their mothers

OBJECTIVE

Congenital Heart Defects (CHD) may be related to nutritional deficiencies affecting the methylation cycle. We aimed to study the metabolic markers of the betaine homocysteine methyl transferase (BHMT) pathway in children with CHD and their mothers compared to children without CHD and their mothers.

MATERIALS AND METHODS

Children with CHD (n=105, age < 3 years) and mothers of 80 of the affected children were studied. The controls were non-CHDs children of comparable age as the CHD group (n=52) and their mothers (n=50). We measured serum or plasma concentrations of the metabolites of the methylation cycle homocysteine (HCY), methylmalonic acid (MMA), cystathionine, S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH), betaine, choline, and dimethylglycine (DMG).

RESULTS

Children with CHD had higher plasma SAM (131 vs. 100 nmol/L) and DMG (8.7 vs. 6.0 μmol/L) and lower betaine/DMG ratio (7.5 vs. 10.2) compared to the controls. Mothers of CHD children showed also higher DMG (6.1 vs. 4.1 µmol/L) and lower betaine/DMG ratio compared with the mothers of the controls. Higher SAM levels were related to higher cystathionine, MMA, betaine, choline, and DMG. MMA elevation in the patients was related to higher HCY, SAM, betaine and DMG.

CONCLUSIONS

Elevated DMG in CHD children and their mothers compared to the controls can indicate upregulation of the BHMT pathway in this disease group. Nutritional factors are related to metabolic imbalance during pregnancy that may be related to worse birth outcome.

Folic acid supplementation use and the MTHFR C677T polymorphism in orofacial clefts etiology: An individual participant data pooled-analysis

BACKGROUND

This study examines gene-environment interaction between the MTHFR C667T polymorphism and folic acid in the etiology of orofacial clefts (OFC). We used a pooled-analytical approach on four studies that used similar methods.

METHODS

We used logistic regression to analyze the pooled sample of 1149 isolated cases and 1161 controls. Fetal and maternal MTHFR C677T genotypes, and maternal periconceptional exposure to smoking, alcohol, vitamin containing folic acid and folic acid supplements were contrasted between the cleft types [non-syndromic clefts lip or without cleft palate (CL(P)) and non-syndromic cleft palate (CP)] and control groups.

RESULTS

There was a reduced risk of CL(P) with maternal folic acid use (p = 0.008; OR = 0.70, 95% CI: 0.65-0.94) and with supplements containing folic acid (p = 0.028, OR = 0.80, 95% CI: 0.65-0.94). Maternal smoking increased the risk of both CL(P) (p < 10 e-3; OR = 1.62, 95% CI: 1.35-1.95) and CP (p = 0.028; OR = 1.38, 95% CI: 1.04-1.83). No significant risk was observed with either maternal or fetal MTHFR C677T genotypes.

CONCLUSION

This individual participant data (IPD) meta-analysis affords greater statistical power and can help alleviate the problems associated with aggregate-level data-sharing. The result of this IPD meta-analysis is consistent with previous reports suggesting that folic acid and smoking influence OFC outcomes.

Lower concentrations of B-vitamin subgroups in the serum and amniotic fluid correlate to cleft lip and palate appearance in the offspring of A/WySn mice

PURPOSE

The pathogenesis and prevention of cleft lip and palate (CL/P) have been studied mainly in clinical and animal experiments. A prophylactic poly-B-vitamin substitution during the first months of pregnancy has provided the most encouraging results for the prevention of CL/P recurrence in families at risk. In vitro studies of the palatal organ in an A/WySn mouse model have confirmed the positive influence of B-vitamins on palatal development. The present animal study was performed to analyze different B-vitamin concentrations in the serum and amniotic fluid of A/WySn mice according to the appearance of CL/P in their offspring.

MATERIAL AND METHODS

Concentrations of different B-vitamins (B1, B2, B3, B5, B6, and folic acid) in serum and amniotic fluid were analyzed by high-performance liquid chromatographic detection. Immunohistochemical staining against thiamin-1 receptor was performed on histologic midface sections of A/WySn fetuses with (n = 12) and without (n = 14) CL/P.

RESULTS

Vitamin B5 (P < .001) and folic acid (P < .004) concentrations in the amniotic fluid of dams with CL/P were significantly lower than in dams without CL/P. Serum concentrations of folic acid (P = .5) and B5 (P = .4) showed no difference between the 2 groups. Dams with CL/P had significantly lower thiamine concentrations in serum (P = .01) and amniotic fluid (P < .001). Histologic midface sections presented high thiamin-1 receptor expression in the palatal shelf of fetuses with CL/P.

CONCLUSION

A decreased use or uptake of some B-vitamin subgroups (B1, B5, and folic acid) in amniotic fluid and serum (vitamin B1) was correlated to an increased cleft appearance in A/WySn mice. The high thiamin-1 receptor expression in the palatal tissue of mouse fetuses with CL/P may be caused by a decreased availability of vitamin B1.