Association of MTHFR (C677T, A1298C) and MTRR A66G polymorphisms with fatty acids profile and risk of neural tube defects.

OBJECTIVE: This study aims to determine if 5,10-methylenetetrahydrofolate reductase (MTHFR C677T and A1298C) and methionine synthase reductase (MTRR A66G) gene polymorphisms were associated with fatty acid (FA) levels in mothers of fetuses with neural tube defects (NTDs) and whether these associations were modified by environmental factors. METHODS: Plasma FA composition was assessed using capillary gas chromatography. Concentrations of studied FA were compared between 42 mothers of NTDs fetuses and 30 controls as a function of each polymorphism by the Kruskal-Wallis nonparametric test. RESULTS: In MTHFR gene C677T polymorphism, cases with (CT + TT) genotype had lower monounsaturated FAs (MUFA) and omega-3 polyunsaturated FA (n-3 PUFA) levels, but higher omega-6 polyunsaturated FAs (n-6 PUFA) and omega-6 polyunsaturated FAs: omega-3 polyunsaturated FAs (n-6:n-3) ratio levels. In MTRR gene A66G polymorphism, cases with (AG + GG) genotype had lower MUFA levels, but higher PUFA and n-6 PUFA levels. Controls with (AG + GG) genotype had lower n-6 PUFA levels. In MTHFR gene C677T polymorphism, cases with smoking spouses and (CT + TT) genotype had lower MUFA and n-3 PUFA levels, but higher PUFA, n-6 PUFA, and n-6:n-3 ratio levels. Cases with (CT + TT) genotype and who used sauna during pregnancy had lower n-3 PUFA levels. In MTRR gene A66G polymorphism, cases with (AG + GG) genotype and who used sauna during pregnancy had higher PUFA and n-6 PUFA levels. CONCLUSIONS: Further research is required to clarify the association of FA metabolism and (MTHFR, MTRR) polymorphisms with NTDs.

Association of MTHFR C677T, MTHFR A1298C, and MTRR A66G Polymorphisms with Neural Tube Defects in Tunisian Parents.

OBJECTIVE: This study aims to investigate the association of 5,10-methylenetetrahydrofolate reductase (MTHFR C677T and A1298C) and methionine synthase reductase (MTRR A66G) gene polymorphisms with neural tube defects (NTDs) in a Tunisian population. METHODS: Genotyping was performed by polymerase chain reaction with restriction fragment length polymorphisms (PCR-RFLPs) using the restriction enzymes. Allele and genotype frequencies were compared between mothers and fathers of fetuses with NTDs with matched controls based on an association analysis using SPSS software. RESULTS: MTHFR (C677T, A1298C) and MTRR A66G polymorphisms were found to be protector factors for NTD fetuses in the mother group. In addition, a combination of the three wild-type alleles C677/A1298/A66 has increased four-fold the incidence of NTDs (p = 0.004, OR = 3.96, 95% CI: 1.53-10.23). In the father group, MTHFR C677T was a risk factor for NTDs. However, no association was found between MTHFR A1298C, MTRR A66G, and the occurrence of this anomaly. The analysis of MTHFR C677T and MTRR A66G polymorphisms has demonstrated a significant difference in vitamin B12 levels between recessive and dominant genotypes in case mothers (p < 0.05). CONCLUSION: Additional studies are required to better understand the roles of parental gene polymorphisms related to folate-homocysteine metabolism in the pathogenesis of NTD.

Association of maternal homocysteine and vitamins status with the risk of neural tube defects in Tunisia: A case-control study.

BACKGROUND: This study was conducted to determine whether low folate and vitamin B12 levels, as well as high homocysteine levels in pregnant women are associated with neural tube defects (NTDs) in Tunisia. METHODS: A total of 75 NTDs pregnancies and 75 matched controls were included in the study. Their vitamin B12, folate, and red blood cell folate concentrations were measured using a radio-immunoassay kit and total homocysteine concentrations were determined using a fluorescent polarization immunoassay. RESULTS: Vitamin B12 and folate concentrations were lower in NTD-affected pregnant women than in controls (respectively, p = 0.009 and p < 0.001). Total homocysteine concentration was significantly higher in the NTDs group than in controls (p = 0.008). In the case group, the folate levels were positively related with vitamin B12 levels (r = 0.54; p < 0.001) and negatively correlated with total homocysteine levels (r = -0.19; p = 0.04). Besides, red blood cell folate levels were positively correlated with folate levels (r = 0.24; p = 0.02) and negatively correlated with total homocysteine levels (r = -0.37; p = 0.001). CONCLUSION: Lower concentrations of folate and vitamin B12 are related to the increased risk of NTDs. Both folate and vitamin B12 intake insufficiency could contribute to the increased risk of NTDs. A dietary supplement, combining folate and vitamin B12, might be an effective measure to decrease the NTDs incidence in Tunisia.

Gender and associated skeletal abnormalities in fetuses with neural tube defects.

OBJECTIVE: To determine the association between gender and skeletal defects in fetuses with NTDs. METHODS: 150 NTD fetuses have been examined in three years' course (01.2006-01.2009) in the Clinic of Fetopathology at the Center for Maternity and Neonatology, Tunis. RESULTS: The most common gender associated anomalies for males are cleft palate, anomalies in the form and attachment of the outer ear and the agenesis of corpus callosum. For women, they are distortions of the spine and "frog" face. CONCLUSION: The proven associations in the study are important indicators in the purposeful search for NTDs in early prenatal ultrasound diagnosis.

Fetopathological aspects of holoprosencephaly.

UNLABELLED: Holoprosencephaly (HPE) is a congenital central nervous system malformation estimated to occur in 1/250 conceptuses and 1/10,000 live births. While the severe forms, which are incompatible with life, are easier to detect in the prenatal period, the milder forms can remain unrecognised. As this can have serious consequences for the pregnancy and malformation carriers it is of crucial importance to find ways of timely detection of this pathological condition. The present study AIMED at finding an association of holoprosencephaly with facial dysmorphia and anomalies of visceral organs that would alert the physician to be very careful in making the prenatal diagnosis, which may require termination of pregnancy by medical indications. MATERIAL AND METHODS: The study included 15 fetuses diagnosed with holoprosencephaly out of 2095 cases analysed post-mortem in the Fetopathology Clinic at the Centre for Maternity and Neonatology in the town of Tunisia over a period of 3 years (Oct. 2006 - Oct. 2009). The fetuses were analysed macro- and microscopically. RESULTS: All forms of holoprosencephaly include elements of facial dysmorphism with the facial phenotypes of cyclopia, cebocephaly and ethmocephaly. It can be associated with specific internal organs anomalies, the hydrocephaly being the most common anomaly of the central nervous system. Our study suggested that holoprosencephaly can be correlated with craniofacial anomalies affecting the midfacial and medium craniovisceral structures. CONCLUSION: The anatomical variations of HPE and the phenotypic facial correlations require a systematic and targeted study of central nervous system.