0000000000300386

AUTHOR

Ana B. García-garcía

Analysis of sequence variations in the LDL receptor gene in Spain: general gene screening or search for specific alterations?

Abstract Background: Familial hypercholesterolemia (FH) is a frequent form of autosomal-dominant hypercholesterolemia that predisposes to premature coronary atherosclerosis. FH is caused by sequence variations in the gene coding for the LDL receptor (LDLR). This gene has a wide spectrum of sequence variations, and genetic diagnosis can be performed by 2 strategies. Methods: Point variations and large rearrangements were screened along all the LDLR gene (promoter, exons, and flanking intron sequences). Results: We screened a sample of 129 FH probands from the Valencian Community, Spain, and identified 54 different LDLR sequence variations. The most frequent (10% of cases) was 111insA, and 60…

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Respiratory chain polymorphisms and obesity in the Spanish population, a cross-sectional study

ObjectiveTo study the association of genes involved in the mitochondrial respiratory chain (MRC) pathway with body mass index (BMI) and obesity risk.DesignThis work studies three cross-sectional populations from Spain, representing three provinces: HORTEGA (Valladolid, Northwest/Centre), SEGOVIA (Segovia, Northwest/centre) and PIZARRA (Malaga,South).SettingForty-eight single nucleotide polymorphisms (SNPs) from MRC genes were selected and genotyped by SNPlex method. Association studies with BMI and obesity risk were performed for each population. These associations were then verified by analysis of the studied population as a whole (3731 samples).ParticipantsA total of 3731 Caucasian indivi…

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Oxidative stress and antioxidant enzyme values in lymphomonocytes after an oral unsaturated fat load test in familial hypercholesterolemic subjects

Oxidative stress (OS) has been observed in conditions affecting the cardiovascular system. Familial hypercholesterolemia (FH) is associated with an increased risk of premature coronary heart disease. In the postprandial state, circulating lipids and lipoproteins can modulate OS status. Our aim was to study the response of lymphomonocyte OS status and reactive oxygen species by-products after an oral unsaturated fat load test (OFLT) in those with FH and to compare this response with that obtained in normolipidemic, normoglycemic subjects. We studied 12 patients with FH and 20 healthy controls. In both groups, lymphomonocyte, oxidized/reduced glutathione ratio, and malondialdehyde were determ…

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Genetic diagnosis of familial hypercholesterolemia in a South European outbreed population: influence of low-density lipoprotein (LDL) receptor gene mutations on treatment response to simvastatin in total, LDL, and high-density lipoprotein cholesterol.

The aims of this study were to examine the presence of mutations in the low-density lipoprotein receptor gene among subjects clinically diagnosed with familial hypercholesterolemia and to analyze whether the molecular diagnosis helps to predict the response to simvastatin treatment in our familial hypercholesterolemia population. Fifty-five probands and 128 related subjects with familial hypercholesterolemia were studied. Genetic diagnosis was carried out following a three-step protocol based on Southern blot and PCR-single strand conformational polymorphism analysis. A randomized clinical trial with simvastatin was conducted in 42 genetically diagnosed subjects with familial hypercholester…

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Semiquantitative multiplex PCR: a useful tool for large rearrangement screening and characterization

Methods presently employed for detection of large rearrangements have several drawbacks, such as the amount of sample and time required, technical difficulty, or the probability of false-negative carriers. Using the low-density-lipoprotein receptor (LDLR) gene, whose mutations are responsible for familial hypercholesterolemia (FH), we have developed a procedure to detect large rearrangements in this gene based on semiquantitative PCR, with important improvements as compared to previous methods. Our method covers the complete LDLR gene and introduces an internal control in the reaction. The procedure discriminates the four different large rearrangements (two deletions and two insertions) tha…

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Influence of LDL receptor gene mutations and the R3500Q mutation of the apoB gene on lipoprotein phenotype of familial hypercholesterolemic patients from a South European population

Few data are available on genotype-phenotype interactions among familial hypercholesterolemia (FH) patients in South European populations and there are no data about the influence of R3500Q mutation on lipoprotein phenotype compared to low-density lipoprotein receptor (LDLR) mutations. The objective of the study is to analyze the influence of mutations in the LDLR and apolipoprotein B (apoB) genes on lipoprotein phenotype among subjects clinically diagnosed of FH living in East Spain. In all, 113 FH index patients and 100 affected relatives were studied. Genetic diagnosis was carried out following a protocol based on Southern blot and PCR-SSCP analysis. A total of 118 FH subjects could be c…

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Determinantes de la lipemia posprandial medida como perfil diurno de triglicéridos en personas no diabéticas con normolipemia

Fundamento y objetivo: Conocer los determinantes clinicos y biologicos de la lipemia posprandial, medida con la autodeterminacion diurna de trigliceridos en sangre capilar (TGc), en personas sin dislipemia ni diabetes. Pacientes y metodo: Hemos estudiado a 76 personas sanas (45 mujeres premenopausicas) con normolipemia y sin diabetes. La determinacion de los TGc se realizo mediante Accutrend® durante 3 dias en 6 puntos establecidos: ayunas, inmediatamente antes y 3 h despues de comer y de cenar, y antes de acostarse. Se midio el area bajo la curva de TGc (ABC-TGc) como expresion de la lipemia posprandial diurna. Resultados: El ABC-TGc fue significativamente mayor en los varones (26,20 [11,0…

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Association of C677T polymorphism in MTHFR gene, high homocysteine and low HDL cholesterol plasma values in heterozygous familial hypercholesterolemia.

Aim: to investigate the association of C677T polymorphism in the methylene tetrahydrofolate reductase (MTHFR) gene, homocysteine plasma values (Hcy), and plasma HDL cholesterol in heterozy-gous familial hypercholesterolemia (hFH).Methods: One hundred and twenty-five hFH subjects were studied. Plasma lipid, lipoprotein, vitamin B12, folic acid and Hcy values were determined. C677T polymorphism in the MTHFR gene was detected by SSCP-PCR. Genetic diagnosis of FH was determined by a three-step protocol using SSCP-PCR, Southern blot, long PCR and automatic sequencing.Results: We found significant differences in plasma HDL-C (CC 1.39±0.34, CT 1.33±0.39 and TT 1.14±0.26 mmol/L, p=0.028) between th…

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Molecular genetics of familial hypercholesterolemia in Spain: Ten novel LDLR mutations and population analysis

Mutations underlying FH in Spain are largely unknown because only a few and limited surveys have been carried out on Spanish FH patients up to now. To gain information on this issue, we have analysed a group of 113 unrelated Spanish FH patients from an eastern area of Spain (Valencian Community). We have screened the LDLR gene by Southern blot and PCR-SSCP analysis to detect large rearrangements and small mutations, respectively. In addition, we have screened the Apo B gene for mutations known to cause FDB by PCR-SSCP analysis. We have identified a total of 47 different mutations in the LDLR gene (5 large rearrangements, and 42 small mutations, which were characterized by DNA sequencing), 1…

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Evaluation of clinical diagnosis criteria of familial ligand defective apoB 100 and lipoprotein phenotype comparison between LDL receptor gene mutations affecting ligand-binding domain and the R3500Q mutation of the apoB gene in patients from a South European population

Familial hypercholesterolemia (FH) and familial defective apoB 100 (FDB) are characterized by increased plasma low-density lipoprotein cholesterol (LDLc) levels and risk of coronary heart disease (CHD). FDB is clinically indistinguishable from FH. The aims of this study were to evaluate clinical diagnosis criteria for FDB and to compare the lipoprotein phenotype between carriers of LDL receptor (LDLR) gene mutations that affect the ligand-binding domain and subjects with the R3500Q mutation in apoB gene. We studied 213 subjects (113 probands) with FH and 19 heterozygous FDB subjects. Genetic diagnosis was determined by following a protocol based on Southern blot and polymerase chain reactio…

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Influence of microsomal triglyceride transfer protein promoter polymorphism -493 GT on fasting plasma triglyceride values and interaction with treatment response to atorvastatin in subjects with heterozygous familial hypercholesterolaemia.

Familial hypercholesterolaemia (FH) is an autosomal dominant disease characterized by elevated levels of low-density lipoprotein-cholesterol (LDL-C). Phenotypic expression is highly variable, being influenced by diet, age, gender, body mass index, apolipoprotein E genotype and type of LDL-receptor gene mutation. Microsomal triglyceride (TG) transfer protein (MTP) is a protein involved in lipid metabolism. Polymorphism MTP -493 GT has been shown to modulate lipid levels in several populations. To analyse the effect of this polymorphism in the lipid phenotype expression of FH and treatment response, we studied a sample of 222 Spanish FH patients, of whom 147 were studied before and after trea…

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Easy One-Step Amplification and Labeling Procedure for Copy Number Variation Detection.

Abstract Background The specific characteristics of copy number variations (CNVs) require specific methods of detection and characterization. We developed the Easy One-Step Amplification and Labeling procedure for CNV detection (EOSAL-CNV), a new method based on proportional amplification and labeling of amplicons in 1 PCR. Methods We used tailed primers for specific amplification and a pair of labeling probes (only 1 labeled) for amplification and labeling of all amplicons in just 1 reaction. Products were loaded directly onto a capillary DNA sequencer for fragment sizing and quantification. Data obtained could be analyzed by Microsoft Excel spreadsheet or EOSAL-CNV analysis software. We d…

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Postprandial Changes in Chemokines Related to Early Atherosclerotic Processes in Familial Hypercholesterolemic Subjects: A Preliminary Study.

Familial hypercholesterolemia (FH) is associated with higher levels of inflammatory mediators such as chemokines, which contribute to an increased risk of premature atherosclerosis in these patients. We studied the response of chemokines related to early atherosclerotic processes during an oral unsaturated fat load test (OFLT) in patients with heterozygous FH and compared this response to normolipidemic and normoglycemic subjects.Blood samples were taken from 12 FH patients and 20 healthy controls with a similar age, gender distribution, and body mass index. Plasma chemokine levels were determined in both groups in a fasting state and at 2, 4, 6, and 8 h after an OFLT using human cytokine m…

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Influencia de las mutaciones HF Valencia 1 y 2 del gen del receptor de LDL sobre la respuesta terapéutica a simvastatina en sujetos con hipercolesterolemia familiar heterocigota caracterizada molecularmente

Fundamento Analizar si el diagnostico molecular de la hipercolesterolemia familiar (HF) ayuda apredecir la respuesta terapeutica a simvastatina, en una poblacion mediterranea del sur de Europa. Sujetos y metodo Hemos estudiado la respuesta terapeutica en 27 sujetos con diagnostico genetico de HF (11 varones) pertenecientes a 8 familias con HF, seleccionadas por muestreo aleatorio entre 30 familias con HF con diagnostico molecular, en un estudio de intervencion sin grupo control con 20 mg/dia de simvastatina. Comparamos las caracteristicas clinicobiologicas entre sujetos clasificados como HF mutaciones nulas (HF Valencia 1 y Valencia 2; n = 11) o HF mutaciones no nulas (n = 16) en situacion …

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