RESUMO
Most consensus recommendations for the genetic diagnosis of neurodevelopmental disorders (NDDs) do not include the use of next generation sequencing (NGS) and are still based on chromosomal microarrays, such as comparative genomic hybridization array (aCGH). This study compares the diagnostic yield obtained by aCGH and clinical exome sequencing in NDD globally and its spectrum of disorders. To that end, 1412 patients clinically diagnosed with NDDs and studied with aCGH were classified into phenotype categories: global developmental delay/intellectual disability (GDD/ID); autism spectrum disorder (ASD); and other NDDs. These categories were further subclassified based on the most frequent accompanying signs and symptoms into isolated forms, forms with epilepsy; forms with micro/macrocephaly and syndromic forms. Two hundred and forty-five patients of the 1412 were subjected to clinical exome sequencing. Diagnostic yield of aCGH and clinical exome sequencing, expressed as the number of solved cases, was compared for each phenotype category and subcategory. Clinical exome sequencing was superior than aCGH for all cases except for isolated ASD, with no additional cases solved by NGS. Globally, clinical exome sequencing solved 20% of cases (versus 5.7% by aCGH) and the diagnostic yield was highest for all forms of GDD/ID and lowest for Other NDDs (7.1% versus 1.4% by aCGH) and ASD (6.1% versus 3% by aCGH). In the majority of cases, diagnostic yield was higher in the phenotype subcategories than in the mother category. These results suggest that NGS could be used as a first-tier test in the diagnostic algorithm of all NDDs followed by aCGH when necessary.
RESUMO
Inherited retinal diseases (IRDs), defined by dysfunction or progressive loss of photoreceptors, are disorders characterized by elevated heterogeneity, both at the clinical and genetic levels. Our main goal was to address the genetic landscape of IRD in the largest cohort of Spanish patients reported to date. A retrospective hospital-based cross-sectional study was carried out on 6089 IRD affected individuals (from 4403 unrelated families), referred for genetic testing from all the Spanish autonomous communities. Clinical, demographic and familiar data were collected from each patient, including family pedigree, age of appearance of visual symptoms, presence of any systemic findings and geographical origin. Genetic studies were performed to the 3951 families with available DNA using different molecular techniques. Overall, 53.2% (2100/3951) of the studied families were genetically characterized, and 1549 different likely causative variants in 142 genes were identified. The most common phenotype encountered is retinitis pigmentosa (RP) (55.6% of families, 2447/4403). The most recurrently mutated genes were PRPH2, ABCA4 and RS1 in autosomal dominant (AD), autosomal recessive (AR) and X-linked (XL) NON-RP cases, respectively; RHO, USH2A and RPGR in AD, AR and XL for non-syndromic RP; and USH2A and MYO7A in syndromic IRD. Pathogenic variants c.3386G > T (p.Arg1129Leu) in ABCA4 and c.2276G > T (p.Cys759Phe) in USH2A were the most frequent variants identified. Our study provides the general landscape for IRD in Spain, reporting the largest cohort ever presented. Our results have important implications for genetic diagnosis, counselling and new therapeutic strategies to both the Spanish population and other related populations.
Assuntos
Distrofias Retinianas/epidemiologia , Distrofias Retinianas/genética , Transportadores de Cassetes de Ligação de ATP/genética , Adulto , Idoso , Estudos de Coortes , Estudos Transversais , DNA/genética , Proteínas da Matriz Extracelular/genética , Proteínas do Olho/genética , Feminino , Testes Genéticos/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Miosina VIIa/genética , Linhagem , Periferinas/genética , Prevalência , Retinose Pigmentar/genética , Estudos Retrospectivos , Espanha/epidemiologiaRESUMO
PURPOSE: To define genotype-phenotype correlations in the largest cohort study worldwide of patients with biallelic ABCA4 variants, including 434 patients with Stargardt disease (STGD1) and 72 with cone-rod dystrophy (CRD). DESIGN: Cohort study. METHODS: We characterized 506 patients with ABCA4 variants using conventional genetic tools and next-generation sequencing technologies. Medical history and ophthalmologic data were obtained from 372 patients. Genotype-phenotype correlation studies were carried out for the following variables: variant type, age at symptom onset (AO), and clinical phenotype. RESULTS: A total of 228 different pathogenic variants were identified in 506 ABCA4 patients, 50 of which were novel. Genotype-phenotype correlations showed that most of the patients with biallelic truncating variants presented with CRD and that these cases had a significantly earlier AO than patients with STGD1. Three missense variants are associated with CRD for the first time (c.1804C>T; p.[Arg602Trp], c.3056C>T; p.[Thr1019Met], and c.6320G>C; p.[Arg2107Pro]). Analysis of the most prevalent ABCA4 variant in Spain, c.3386G>T; p.(Arg1129Leu), revealed that is correlated to STGD1, later AO, and foveal sparing. CONCLUSIONS: Our study, conducted in the largest ABCA4-associated disease cohort reported to date, updates the genotype-phenotype model established for ABCA4 variants and broadens the mutational spectrum of the gene. According to our observations, patients with ABCA4 presenting with 2 truncating variants may first present features of STGD1 but eventually develop rod dysfunction, and specific missense variants may be associated with a different phenotype, underscoring the importance of an accurate genetic diagnosis. Also, it is a prerequisite for enrollment in clinical trials, and to date, no other treatment has been approved for STGD1.
Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Distrofias de Cones e Bastonetes/genética , Mutação de Sentido Incorreto , Doença de Stargardt/genética , Adulto , Idade de Início , Alelos , Estudos de Coortes , Distrofias de Cones e Bastonetes/diagnóstico , Eletrorretinografia , Feminino , Estudos de Associação Genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Repetições de Microssatélites/genética , Pessoa de Meia-Idade , Linhagem , Polimorfismo de Nucleotídeo Único/genética , Espanha , Doença de Stargardt/diagnóstico , Tomografia de Coerência Óptica , Acuidade Visual/fisiologia , Adulto JovemRESUMO
PURPOSE: We aimed to unravel the molecular basis of sporadic retinitis pigmentosa (sRP) in the largest cohort reported to date. DESIGN: Case series. PARTICIPANTS: A cohort of 877 unrelated Spanish sporadic cases with a clinical diagnosis of retinitis pigmentosa (RP) and negative family history. METHODS: The cohort was studied by classic genotyping or targeted next-generation sequencing (NGS). Multiplex ligation-dependent probe amplification (MLPA) and array-based comparative genomic hybridization were performed to confirm copy number variations detected by NGS. Quantitative fluorescent polymerase chain reaction was assessed in sRP cases carrying de novo variants to confirm paternity. MAIN OUTCOME MEASURES: The study of the sRP cohort showed a high proportion of causal autosomal dominant (AD) and X-linked (XL) variants, most of them being de novo. RESULTS: Causative variants were identified in 38% of the patients studied, segregating recessively in 84.5% of the solved cases. Biallelic variants detected in only 6 different autosomal recessive genes explained 50% of the cases characterized. Causal AD and XL variants were found in 7.6% and 7.9% of cases, respectively. Remarkably, 20 de novo variants were confirmed after trio analysis, explaining 6% of the cases. In addition, 17% of the solved sRP cases were reclassified to a different retinopathy phenotype. CONCLUSIONS: This study highlights the clinical utility of NGS testing for sRP cases, expands the mutational spectrum, and provides accurate prevalence of mutated genes. Our findings evidence the underestimated role of de novo variants in the etiology of RP, emphasizing the importance of segregation analysis as well as comprehensive screening of genes carrying XL and AD variants in sporadic cases. Such in-depth study is essential for accurate family counseling and future enrollment in gene therapy-based treatments.
Assuntos
Retinose Pigmentar/genética , Adulto , Estudos de Coortes , Hibridização Genômica Comparativa , Variações do Número de Cópias de DNA , Análise Mutacional de DNA/métodos , Feminino , Genes Recessivos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Linhagem , FenótipoRESUMO
PURPOSE: The aim of the study was to analyze the frequency and certain epidemiological characteristics of a consecutive series of conjoined twins born in Spain. MATERIAL AND METHODS: We used data from the Spanish Collaborative Study of Congenital Malformations for the period April 1976 to 2006. Because the Spanish law permitting voluntary termination of pregnancies (TOP) when the fetus presented malformations was effective by the end of 1985, we analyzed the data in 4 periods, 2 before 1986 and 2 after. During the first period (1976-1979) only live births were recorded, whereas both still and live births were included in the other three (1980-1985, 1986-1995, and 1996-2006). In the present study, the cases were classified as symmetrical (16 pairs) and asymmetrical (1 pair) conjoined twins. Each pair of conjoined twins was considered as only one case for calculations, regardless of the type of union. RESULTS: Among a total of 2,281,604 consecutive births between 1980 and 2006, there were a total of 15 cases of symmetrical conjoined twins giving a frequency of 0.70 per 100,000 (1/152,107), whereas there was only 1 stillborn asymmetrical conjoined twin pair (0.04/100,000). Among the 13,418 consecutive stillborns surveyed, 6 cases of conjoined twins were identified (either symmetrical or asymmetrical) giving a frequency of 44.72 per 100,000, and 11 pairs were identified among the 2,425,583 total live births surveyed during the first period 1976 to 1979, a frequency of 0.45 per 100,000. Thus, the frequency among stillborn infants is 99.34 times higher than that observed among live births. However, the frequency for the total births (3 last periods) showed a decreasing trend from 1.47 per 100,000 birth in the first period (1980-1985) when TOP was illegal, to a value of 0.09 per 100,000 in the last period, more than 16-fold lower, probably because of the TOP of affected fetuses. Therefore, we consider that the frequencies observed in the period 1980 to 1985 are the basal values in our population. The most frequent type observed was thoracopagus, with an overall prevalence at birth of 0.44 per 100,000 (1/228,160) from 1980 to 2006, representing 58.82% of the total population of symmetric conjoined twin pairs. Diprosopus pairs were the next most common group (11.76%). Most of the cases were females (4 males/11 females), and although this appeared to be mainly because of the thoracopagus pairs (males-females, 2:8), in such a small number of cases, it is not possible to determine the ratios for the other groups. Gestational age was significantly shorter than in control twins for each type studied. CONCLUSIONS: We conclude that it is incorrect to consider that all types of conjoined twins have the same epidemiological characteristics, such as the frequency at birth. The differences observed may be related with the distinct embryo-fetal mortality of each type of conjoined twins in different populations, and the sex ratio, among others.
Assuntos
Anormalidades Múltiplas/epidemiologia , Causas de Morte , Natimorto/epidemiologia , Gêmeos Unidos/patologia , Anormalidades Múltiplas/diagnóstico , Anormalidades Múltiplas/cirurgia , Aborto Terapêutico , Feminino , Humanos , Incidência , Recém-Nascido , Masculino , Diagnóstico Pré-Natal , Sistema de Registros , Estudos Retrospectivos , Espanha/epidemiologia , Análise de Sobrevida , Gêmeos Unidos/fisiopatologiaRESUMO
OBJECTIVE: To assess the safety of calcium channel blockers during the first trimester of pregnancy. STUDY DESIGN: A multicenter (n=11), prospective observational study of the European Network of Teratology Information Services (ENTIS). The rate of major birth defects was compared between a cohort of pregnant women exposed to calcium channel blockers during the first trimester (n=299) and a control group not exposed to potential teratogens (n=806). RESULTS: Major birth defects were not more common in the study group than in the control group. Birth weight was significantly lower in exposed term newborns. There were more preterm infants in the study group than in the control group (23.8% vs. 6.5%). These adverse effects are more likely due to the underlying disease than to the medication. CONCLUSION: This study suggests that calcium channel blockers during the first trimester of pregnancy do not represent a major teratogenic risk.
Assuntos
Anormalidades Induzidas por Medicamentos/etiologia , Aborto Espontâneo/etiologia , Bloqueadores dos Canais de Cálcio/efeitos adversos , Nascimento Prematuro/etiologia , Anormalidades Induzidas por Medicamentos/epidemiologia , Aborto Espontâneo/epidemiologia , Adolescente , Adulto , Peso ao Nascer , Europa (Continente)/epidemiologia , Feminino , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Israel/epidemiologia , Pessoa de Meia-Idade , Gravidez , Primeiro Trimestre da Gravidez , Nascimento Prematuro/epidemiologia , Estudos ProspectivosRESUMO
BACKGROUND AND OBJECTIVE: Studies on different populations have shown a great variability of the frequencies of different polymorphisms in genes acting in the folate cycle. The present study was aimed to analyze the frequency in the Spanish population of each genotype combination of four polymorphisms, one of them -1561C-T of the glutamate carboxypeptidase II (GCPII) gene- being the first time that is studied in Spain. The study included a meta-analysis of the published data. SUBJECTS AND METHOD: Using the Spanish Collaborative Study of Congenital Malformations (ECEMC) Network, blood samples of 190 mother-child couples with newborns without any congenital defect, were obtained from 15 Spanish autonomous regions. The study polymorphisms were the 677C-T and 1298A-C polymorphisms of the methylenetetrahydrofolate reductase (MTHFR), the 66A-G of the methionine synthase reductase (MTRR), and the 1561C-T polymorphism of the GCPII gene. To estimate the range for the population frequencies, 99% confidence intervals were calculated. RESULTS: The frequencies observed in our country were significantly different from others, being similar to those obtained in countries of the Mediterranean European area. The 1561C-T polymorphism of the GCPII gene has a frequency in Spain of 5.11%, which is also similar to the values observed in France (5%) and in Italy (6%). On the other hand, the frequency of the genotypes CTCC, TTAC is quite few, while the genotype TTCC was not observed in any mother or infants. A meta-analysis was performed for a big sample (23,612 individuals) and the results showed that with a 99% of probability the values for the genotype combinations CTCC, TTAC, and TTCC were within 0.10-0.24; 0.20-0.36; and 0.003-0.05, respectively. CONCLUSIONS: Our results are important to further analyze the relationship with some health problems and individual susceptibilities. Indeed, considering the published observations of the structure and function of the MTHFR enzyme, it is understandable that those genotype combinations that are quite little frequent, may be related to the embryo-fetal viability, and to the life style of each population.
Assuntos
Antígenos de Superfície/genética , Ferredoxina-NADP Redutase/genética , Ácido Fólico/metabolismo , Glutamato Carboxipeptidase II/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Feminino , Genótipo , Humanos , Recém-Nascido , MãesRESUMO
BACKGROUND: Hypospadias is one of the most frequently occurring genital anomalies described in infants prenatally exposed to valproic acid (VA). However, to our knowledge, only one publication has studied a potential causal relationship between VA and hypospadias, only estimating the unadjusted global risk. Here we present the results of a multivariate case-control study aimed at analysing and quantifying the specific risk of hypospadias in newborn infants exposed to VA during the first trimester of pregnancy. METHODS: The data analysed here were derived from the Spanish Collaborative Study of Congenital Malformations (ECEMC), an ongoing, hospital-based, case-control study and surveillance system in which collaborating paediatricians identify case and control infants. The paediatricians collect the same data for both case and control infants, blinded to information on any prenatal exposure. The information includes 312 items related to many prenatal exposures, including drug exposure, reproductive and family history, and other characteristics. The sample analysed included 2,393 infants with hypospadias and 12,465 male controls. RESULTS: The results showed that the unadjusted risk of hypospadias in infants prenatally exposed to VA was 5.23 (95% CI 2.31, 11.86; p < 0.00001). Once adjusted for 13 potential confounding factors using conditional logistic regression analyses, the value of the risk was of a similar magnitude (odds ratio = 5.71; 95% CI 1.78, 18.36; p = 0.003). In addition, the frequency of hypospadias in the study population was approximately 1.8/1000 births. This allowed us to calculate the specific risk for an infant with hypospadias to be born to an exposed mother, which was 1 child in 97 births to mothers using VA during the first trimester of pregnancy. We consider this information much more useful for risk assessment than the risk value itself. CONCLUSIONS: An alteration of placental gonadotrophic stimulation caused by changes in gonadotropin-releasing hormone release produced by the effects of VA on GABA is a possible pathogenic mechanism. Our results support the relationship between prenatal exposure to VA and hypospadias.
Assuntos
Anticonvulsivantes/efeitos adversos , Hipospadia/induzido quimicamente , Hipospadia/epidemiologia , Primeiro Trimestre da Gravidez/fisiologia , Ácido Valproico/efeitos adversos , Anticonvulsivantes/uso terapêutico , Estudos de Casos e Controles , Epilepsia/tratamento farmacológico , Epilepsia/epidemiologia , Feminino , Humanos , Recém-Nascido , Modelos Logísticos , Masculino , Gravidez , Vigilância de Produtos Comercializados , Risco , Espanha/epidemiologia , Ácido Valproico/uso terapêuticoRESUMO
Most studies associating different types of malformations with the presence of a single umbilical artery (SUA) are based on small and selected series. Here, we present the results of a study aimed at identifying the most frequent, and the most specific anomalies related to SUA. We analyzed 19,909 consecutive newborn infants with congenital malformations, from the Spanish Collaborative Study of Congenital Malformations (ECEMC). To estimate the specificity of the relationship of different congenital defects with SUA, we calculated their relative frequencies (RF) by dividing their frequency in infants with SUA by the corresponding frequency in newborn infants without SUA. Using the different levels of the ECEMC coding system, we calculated the RFs in three steps: (a) a group of individual congenital defects, (b) different groups of malformed infants, and (c) each individual malformation by its clinical presentation in some of the studied groups of malformed infants. The defects most specifically associated with SUA were bilateral renal agenesis and imperforate anus, followed by unilateral renal agenesis, and vertebral defects, the RF of which indicated that they were between 7.99 and 9.93 times more frequent among malformed infants with SUA than among malformed infants without SUA. However, these defects were not as frequent in the group of infants with SUA, as cardiovascular anomalies. Regarding the association of SUA in the groups of malformed infants, the most specific groups were body stalk defects and sirenomelia. Finally, we analyzed the association of the individual defects by different groups of malformed infants in order to identify if the individual defects are associated with SUA in any type of clinical presentation, and in relation to some groups of infants with genetic disorders. The results, together with the embryonic development of the umbilical cord, strongly suggest that not all cases of SUA have the same cause, and that all previously suggested mechanisms may be possible but with different frequencies.
Assuntos
Anormalidades Múltiplas/epidemiologia , Anormalidades Múltiplas/patologia , Artérias Umbilicais/anormalidades , Estudos de Casos e Controles , Feminino , Humanos , Recém-Nascido , Masculino , Valor Preditivo dos Testes , Espanha/epidemiologiaRESUMO
Selective Serotonin Reuptake Inhibitors (SSRIs) have become the drug of choice for the treatment of depression and have shown to be effective in the treatment for other mental disorders. Recently, several articles have reported about the adverse effects observed in newborns after maternal exposure to these drugs during the last trimester of pregnancy. In this work, a review of literature is presented, regarding the above mentioned adverse effects. Moreover, some guidelines for the rational use of these drugs during the last trimester of pregnancy and for the management of prenatally exposed newborns are provided.
Assuntos
Transtorno Depressivo/tratamento farmacológico , Síndrome de Abstinência Neonatal/etiologia , Síndrome de Abstinência Neonatal/prevenção & controle , Complicações na Gravidez/tratamento farmacológico , Inibidores Seletivos de Recaptação de Serotonina/efeitos adversos , Síndrome da Serotonina/etiologia , Adulto , Feminino , Humanos , Recém-Nascido , Gravidez , Terceiro Trimestre da Gravidez , Síndrome da Serotonina/prevenção & controle , Inibidores Seletivos de Recaptação de Serotonina/intoxicação , Inibidores Seletivos de Recaptação de Serotonina/uso terapêuticoRESUMO
BACKGROUND AND OBJECTIVE: To study the effects of antenatal corticosteroids treatment to promote fetal lung maturation, on fetal growth, depending on the number of the courses administered. PATIENTS AND METHOD: The study was based on data from the Spanish Collaborative Study of Congenital Malformations (ECEMC), analysing a sample of 29,557 singleton liveborn infants without congenital defects. An stratified analysis by gestational age was performed to compare the weight, length and head circumference at birth, in the exposed and unexposed infants to dexamethasone/betamethasone. To control confounding factors (year of birth, maternal age, gestational age, parity, maternal smoking and/or alcohol consumption, gestational diabetes, non-gestational diabetes and other maternal chronic diseases) we used a general linear model with random effects, being the randomised variable the place of birth. RESULTS: The exposure to more than one course of antenatal corticosteroids resulted in a significant reduction of birth weight, length and head circumference in singleton preterm infants. The birth weight decreased by 22% (p < 0.0001), the length 5% (p = 0.002) and the head circumference 6% (p = 0.0005). The treatment with only one course reduced also significantly the weight and length but not the head circumference. In addition, we observed a significant interaction between the treatment and gestational age at birth indicating that the effect of corticosteroids is stronger in the most premature babies. CONCLUSIONS: In this retrospective analysis, the antenatal exposure to corticosteroids to promote fetal maturation is associated with diminished weight, length and head circumference in the premature newborn infant. This negative effect was greater in those premature babies exposed to multiple courses.
Assuntos
Peso ao Nascer/efeitos dos fármacos , Glucocorticoides/efeitos adversos , Pulmão/crescimento & desenvolvimento , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Adulto , Antropometria , Estatura/efeitos dos fármacos , Estudos de Casos e Controles , Feminino , Idade Gestacional , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro , Pulmão/efeitos dos fármacos , GravidezRESUMO
Vitamin K antagonists (VKA) are known to act as teratogens; however, there is still uncertainty about the relative risk for birth defects and the most sensitive period. In a multi-centre (n = 12), observational, prospective study we compared 666 pregnant women exposed to phenprocoumon (n = 280), acenocoumarol (n = 226), fluindione (n = 99), warfarin (n = 63) and phenindione (n = 2) to a non-exposed control group (n = 1,094). Data were collected by institutes collaborating in the European Network of Teratology Information Services (ENTIS) during individual risk counselling between 1988 and 2004. Main outcome measures were coumarin embryopathy and other birth defects, miscarriage rate, birth-weight, and prematurity. The rate of major birth defects after 1st trimester exposure was significantly increased (OR 3.86, 95% CI 1.86-8.00). However, there were only two coumarin embryopathies (0.6%; both phenprocoumon). Prematurity was more frequent (16.0% vs. 7.6%, OR 2.61, 95% CI 1.76-3.86), mean gestational age at delivery (37.9 vs.39.4, p<0.001), and mean birth weight of term infants (3,166 g vs. 3,411 g; p < 0.001) were lower compared to the controls. Using the methodology of survival analysis, miscarriage rate reached 42% vs. 14% (hazard ratio 3.36; 95% CI 2.28-4.93). In conclusion, use of VKA during pregnancy increases the risk of structural defects and other adverse pregnancy outcomes. The risk for coumarin embryopathy is, however, very small, in particular when therapy during the 1(st) trimester did not take place later than week 8 after the 1(st) day of the last menstrual period. Therefore, elective termination of a wanted pregnancy is not recommended if (inadvertent) exposure took place in early pregnancy. Close follow-up by the obstetrician including level II ultrasound should be recommended in any case of VKA exposure during pregnancy.
Assuntos
Anormalidades Induzidas por Medicamentos , Aborto Espontâneo/etiologia , Anticoagulantes/efeitos adversos , Peso ao Nascer/efeitos dos fármacos , Doenças Fetais/etiologia , Resultado da Gravidez , Vitamina K/antagonistas & inibidores , Aborto Induzido , Acenocumarol/efeitos adversos , Sistemas de Notificação de Reações Adversas a Medicamentos , Feminino , Idade Gestacional , Humanos , Fenindiona/efeitos adversos , Fenindiona/análogos & derivados , Femprocumona/efeitos adversos , Gravidez , Primeiro Trimestre da Gravidez , Nascimento Prematuro/etiologia , Estudos Prospectivos , Varfarina/efeitos adversosRESUMO
This study was aimed at analyzing the effect of mutations in three non-synonymous SNP genes (677C > T and 1298A > C of the methylenetetrahydrofolate reductase (MTHFR) gene, and 66A > G in the MTRR gene) on total plasmatic homocysteine (Hcy), in 91 mothers of Down syndrome (DS) infants and 90 control mothers. The comparison of both groups of mothers is a new way to determine if those mutations and their interactions increase the risk for DS. Material came from the case-control network of the Spanish Collaborative Study of Congenital Malformations (ECEMC). Using a general lineal model in a backwards step, we performed the analyses including the different mutations, maternal age, the fact that each mother had a DS or a control infant, and all possible interactions of these variables, in the models, being maternal Hcy the continuous dependent variable. In another model, maternal folic acid intake during the third trimester of pregnancy was added. The results from both models were essentially the same: Hcy levels variability differs from case mothers to control ones, the presence of the MTHFR1298A > C polymorphism also affects significantly the Hcy variance, as it does the statistical interaction between the mutations MTRR66A > G and MTHFR1298A > C in the mother. In this sense, the interaction between different polymorphisms may totally modify their individual effects, and some of those effects are different in mothers of DS children and in controls' mothers. For instance, only two mutations in MTRR66 (GGAA) in mothers of control infants increase the reference maternal Hcy level in 4.66 units, and the individual effect of the genotype with only two mutations in the MTHFR1298 gene (AACC) increases the reference Hcy level in 12.74 units. However, the presence of the four mutations (GGCC) interacts giving a statistically significant decrease in 6.00 units in the level of Hcy in control mothers. On the contrary, in mothers of DS infants, the sole presence of two mutations in one of these two genes decreases the levels of Hcy (-2.31 units for GGAA genotype, and -3.43 units for AACC genotype), while the presence of the four mutations (GGCC) increases Hcy in 9.53 units. Taking into consideration that in the one-carbon metabolism cystathionine beta-synthase (CBS) catalyzes Hcy in an irreversible way, and that CBS gene is located in chromosome 21, fetuses and infants with DS have functional folate deficiency due to overexpression of CBS. This fact, as well as others influencing Hcy levels (such as nutrients interactions and lifestyle), together with the fetal genotype, suggest that their relationship with DS could be through an effect on fetal survival up to birth. Three possible mechanisms are considered by evaluating the results in the light of the present knowledge on cytology and molecular biology.
Assuntos
Síndrome de Down/genética , Ferredoxina-NADP Redutase/genética , Homocisteína/sangue , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Nucleotídeo Único , Estudos de Casos e Controles , Feminino , Ferredoxina-NADP Redutase/metabolismo , Ácido Fólico/administração & dosagem , Genótipo , Humanos , Lactente , Masculino , Metilenotetra-Hidrofolato Redutase (NADPH2)/metabolismo , Mães , Mutação , Análise de Regressão , Fatores de Risco , S-Adenosil-Homocisteína/sangue , S-Adenosilmetionina/sangueRESUMO
BACKGROUND AND OBJECTIVE: The information about the convenience of non-smoking during pregnancy has increased in recent years. For this reason, we studied weather there has been any variation in smoking habits by pregnant women in Spain. SUBJECTS AND METHOD: We used data from 31,056 mothers of infants without congenital defects, from all the Spanish Autonomic Regions. These data had been collected with the same methodology all over the country. The evolution of maternal smoking habit was analyzed by years, Autonomic Regions and maternal characteristics. RESULTS: During the last years of the study (1995-2002), 30.31% of mothers smoked during pregnancy, with variations among different ethnic groups. It was observed a secular increase in the prevalence of smoker mothers from 1978 to 1991, which was further stable in about 27-28%. There was no secular decrease in the analyses by maternal age, number of cigarettes, and Autonomic Regions. Only smoker mothers with higher educational levels diminished smoking in 1993, with it being stable in about 23%. Mothers younger than 25 years were the heaviest smokers in all the years of the study. We confirmed a close relationship between tobacco, alcohol and illegal drugs consumption. CONCLUSIONS: Our data indicate that the prevalence of women smoking during pregnancy has not diminished over the years or by Autonomic Regions, although 19.19% of smoker pregnant women quit smoking during the first months of pregnancy. Moreover, the heaviest smoker mothers were the youngest ones in all the years of the study. These results show the need to increase the information for women so that they quit smoking before pregnancy.
Assuntos
Fumar/epidemiologia , Adulto , Feminino , Humanos , Gravidez , Fumar/tendências , Abandono do Hábito de Fumar/estatística & dados numéricos , Espanha/epidemiologiaRESUMO
BACKGROUND AND OBJECTIVE: Fertility treatments, multiple deliveries and caesarean sections are related to maternal age. Because maternal age has increased in Spain, it can also be expected an increase in these variables. We analyzed their evolution over the time and by maternal age, either globally and by Spanish Autonomous Communities. SUBJECTS AND METHOD: We studied a sample of 30,956 mothers of non-malformed newborn infants from all over Spain. STUDY PERIOD: between 1977 and June 2002. RESULTS: The percentage of fertility treatments shows a statistically significant increasing trend in all of the maternal ages groups. However, this was higher in mothers older than 34 years, among whom the frequency of multiple deliveries also increased (p = 0.01). The same trends were observed by Spanish Autonomous Communities, yet with differences between them. In the Comunidad Valenciana, we identified the highest frequency of fertility treatments, while the highest mean maternal age was observed in Aragón. Galicia has one of the lowest proportions of multiple deliveries, while the percentage of fertility treatments is similar to other regions. The percentage of caesarean sections (over 25%, globally) shows a statistically significant increasing trend in all the maternal ages groups, the highest one being among mothers older than 39 years. CONCLUSIONS: The observed increasing maternal age implies a higher use of fertility treatments, multiple deliveries and caesarean sections. All these variables show statistically significant variations between Spanish Autonomous Communities and over the time.
Assuntos
Cesárea/estatística & dados numéricos , Gravidez Múltipla/estatística & dados numéricos , Técnicas de Reprodução Assistida/estatística & dados numéricos , Adulto , Feminino , Fármacos para a Fertilidade Feminina , Humanos , Infertilidade Feminina/terapia , Idade Materna , Gravidez , Espanha/epidemiologiaRESUMO
BACKGROUND: The classic clinical criteria for the diagnosis of fetal alcohol syndrome (FAS) include a "characteristic" facial appearance, pre- and postnatal growth deficiency, microcephaly, mental retardation, and occasional major malformations. However, diagnostic constraints, especially in the newborn period, lead to an underestimate of their prevalence. We report an epidemiological study of the potential risk of congenital defects in the offspring of mothers who ingested different sporadic and daily amounts of alcohol during pregnancy. METHODS: The study was based on the data from the ECEMC hospital-based case-control study and surveillance system, with a methodology aimed not only at the surveillance of congenital anomalies, but also at investigating their characteristics, clustering, and causes. For the purposes of this study, we considered as exposed those infants whose mothers reported the ingestion of any amount of alcohol during gestation (4705 mothers of cases and 4329 mothers of controls), and classified them into five groups according to their levels of alcohol consumption. Two groups consisted of mothers who consumed increasing sporadic levels and the other three consisted of mothers who consumed increasing daily levels of alcohol. RESULTS: Our study showed that even low sporadic doses of alcohol consumption during pregnancy may increase the risk of congenital anomalies in the offspring and that this risk increases with increasing levels of alcohol exposure. CONCLUSIONS: The results of our study suggest that it is necessary to generalize the preventive norm and recommend complete abstinence from alcohol during gestation. Birth Defects Research (Part A), 2004.