J Fernandez-Piqueras

Publications (8)41.17 Total impact

• Article: Association of common genetic variants with risperidone adverse events in a Spanish schizophrenic population.

  B Almoguera, R Riveiro-Alvarez, J Lopez-Castroman, P Dorado, C Vaquero-Lorenzo, J Fernandez-Piqueras, A Llerena, F Abad-Santos, E Baca-García, R Dal-Ré, C Ayuso
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  ABSTRACT: Risperidone non-compliance is often high due to undesirable side effects, whose development is in part genetically determined. Studies with genetic variants involved in the pharmacokinetics and pharmacodynamics of risperidone have yielded inconsistent results. Thus, the aim of this study was to investigate the putative association of genetic markers with the occurrence of four frequently observed adverse events secondary to risperidone treatment: sleepiness, weight gain, extrapyramidal symptoms and sexual adverse events. A series of 111 schizophrenia inpatients were genotyped for genetic variants previously associated with or potentially involved in risperidone response. Presence of adverse events was the main variable and potential confounding factors were considered. Allele 16Gly of ADRB2 was significantly associated with a higher risk of sexual adverse events. There were other non-significant trends for DRD3 9Gly and SLC6A4 S alleles. Our results, although preliminary, provide new candidate variants of potential use in risperidone safety prediction.The Pharmacogenomics Journal advance online publication, 3 January 2012; doi:10.1038/tpj.2011.57.
  The Pharmacogenomics Journal 01/2012; · 4.54 Impact Factor
• Article: No association between the Ser9Gly polymorphism of the dopamine D3 receptor gene and schizophrenia in a Spanish sample.

  C Vaquero Lorenzo, E Baca-Garcia, M Diaz Hernandez, C Botillo Martin, M M Perez-Rodriguez, M D Saiz-Gonzalez, P Fernández, F J Quintero Gutierrez, J Saiz-Ruiz, J Fernandez Piqueras, J L Gonzalez de Rivera, J de Leon
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  ABSTRACT: This study aims to further evaluate the controversial association between the Ser9Gly polymorphism in codon 9 of the D3 dopamine receptor gene (DRD3) and schizophrenia in psychiatric inpatients acutely hospitalized in two general hospitals in Madrid, Spain. The Ser9Gly polymorphism of the DRD3 was examined in 178 schizophrenic patients, 286 patients with other psychiatric diagnoses, and 132 controls recruited. Genotype frequencies were in Hardy-Weinberg equilibrium. No association was found between schizophrenia and the Ser9Gly polymorphism of the D3 dopamine receptor gene.
  American Journal of Medical Genetics Part B Neuropsychiatric Genetics 05/2007; 144B(3):344-6. · 3.70 Impact Factor
• Article: New GABAA receptor alpha5 subunit gene polymorphism that may confound genotyping.

  C Vaquero, E Baca-Garcia, C Diaz-Sastre, M M Perez-Rodriguez, M Navio Acosta, J Saiz-Ruiz, J de Leon, J Fernandez-Piqueras
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  ABSTRACT: We report the discovery of a new GABAA receptor alpha5 subunit gene polymorphism close to the polymorphism described by Glatt et al. (GT)5GCGTGC(GT)21. This new polymorphism is of great importance, because it means that non-denaturing acrylamide gels used to separate the different alleles of the polymorphism described by Glatt et al. cannot distinguish an allele with the sequence: (GT)4GCGTGC(GT)n from another allele with the sequence: (GT)4(GCGT)4GC(GT)(n-6). These gel fragments are separated by size, which would be the same in these two cases. An alternative would be to use an analysis method that can detect base changes, for instance, single strand conformation polymorphism (SSCP) or denaturing gradient gel electrophoresis (DGGE).
  American Journal of Medical Genetics Part B Neuropsychiatric Genetics 09/2004; 129B(1):27-8. · 3.70 Impact Factor
• Article: Pathological gambling and DNA polymorphic markers at MAO-A and MAO-B genes.

  A Ibañez, I Perez de Castro, J Fernandez-Piqueras, C Blanco, J Saiz-Ruiz
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  ABSTRACT: This study was conducted to detect a possible association of MAOA and/or MAOB genes with pathological gambling (PG). DNA polymorphisms in MAOA and MAOB genes were screened by molecular analysis in 68 individuals (47 males and 21 females) meeting ICD-10 and DSM-IV criteria for pathological gambling and 68 healthy comparison controls matched for age and sex. There were no significant differences between pathological gamblers and healthy volunteers in overall allele distribution at the MAOA gene polymorphism. However there was a significant association between allele distribution and the subgroup of severe male gamblers (n = 31) compared to the males in the group of healthy volunteers (chi2 = 5246; df = 1; P < 0.05 [Bonferroni corrected]). No association was found between the MAOB polymorphic marker and PG. Allele variants at the MAOA, but not the MAOB gene may be a genetic liability factor in PG, at least in severe male gamblers. Molecular Psychiatry(2000) 5, 105-109.
  Molecular Psychiatry 01/2000; 5(1):105-9. · 13.67 Impact Factor
• Article: Hypermethylation of a 5' CpG island of p16 is a frequent event in non-Hodgkin's lymphoma.

  B Martinez-Delgado, J Fernandez-Piqueras, M J Garcia, E Arranz, J Gallego, C Rivas, M Robledo, J Benitez
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  ABSTRACT: Hypermethylation of a 5' CpG island of p16 gene has been recently described as a possible way of inactivation of this tumor suppressor gene, alternative to deletions and mutations. We have investigated if hypermethylation of a 5' CpG island of p16 occurs in non-Hodgkin's lymphoma (NHL) and normal lymphoid tissue. A total of 82 NHLs were examined for p16 methylation by Southern blot and PCR analysis. Hypermethylation was detected in approximately 20% of B cell lymphomas of both low and high grade and in 15% of T cell NHL. The highest rate of p16 gene methylation in tumors was found among MALT (mucosa-associated lymphoid tissue) lymphomas in which the percentage of cases with p16 gene methylation reached 67%. However, normal lymphoid tissue was always unmethylated at p16 locus. These results indicate that p16 gene methylation is a frequent event in NHLs, mainly in MALT lymphomas, and suggest that it could be an important mechanism of inactivation of this gene.
  Leukemia 04/1997; 11(3):425-8. · 9.56 Impact Factor
• Article: Non-uniform distribution of methylatable CCGG sequences on human chromosomes as shown by in situ methylation.

  C Sentís, P Ludeña, J Fernandez-Piqueras
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  ABSTRACT: We carried out in situ methylation of human chromosomes with the HpaII methylase using [3H]methyl-S-adenosyl-L-methionine as the methyl group carrier. Autoradiographs localising [3H]methyl groups show methylatable CCGG sequences in the R-bands as well as in the short arms of the acrocentric chromosomes that include ribosomal DNA. The strongest labelling was observed over a subset of R-bands, including T-bands. Since methylatable CCGG sequences are representative of the unmethylated fraction of DNA, we suggest that differences in the degree of DNA methylation could be involved in the structure and function of chromosomal bands.
  Chromosoma 04/1993; 102(4):267-71. · 3.85 Impact Factor
• Article: Chromosomal location of the active NORs in theSteropleurus martorelli complex

  J. Fernandez-Piqueras, A. Rodriguez Campos, C. Sentis Castaño, E. Rojo Garcis
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  ABSTRACT: The chromosomal location of the active NORs has been analyzed by a silver impregnation procedure in theSteropleurus martorelli complex. A primary NOR, which is always present at the first meiotic prophase, has been found in each of the four described races. In addition to this, all races possess one or two secondary NORs which are less active than the former and can be occasionally shown. Usually only one of the two homologous chromosomes has been found to be involved with nucleolus organisation.These results are discussed in relation to hypotheses on the chromosome differentiation of this species complex.
  Genetica 12/1982; 61(1):9-12. · 2.15 Impact Factor
• Article: Sex chromosome evolution in the polytypic species Pycnogaster cucullata

  J Fernandez-Piqueras, A Rodriguez Campos, C Sentis Castaño, E Rojo Garcia
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  ABSTRACT: Pycnogaster cucullata (Charp.) is a polytypic species of Tettigonioidea having both X0 and neo XY populations. Moreover the neo XY populations are themselves of two distinct types referred to as neo XY1 and neo XY2.A comparison between the X0 state and the two different neo XY systems, using C-banding and silver staining techniques, has served to clarify the differentiation of the two neo XY systems. In both cases, a centric fusion between the progenitor M2 chromosome, the second largest autosome, and the X of the X0 form has been accompanied by loss of an active NOR in the neo Y, which is the direct derivative of the M2. In both categories of neo XY sex bivalents, a secondary construction appears in the distal region of the XL limb, which gives a silver reaction similar to that observed at the centromeres. The neo XY2 system is distinctive in two respects in comparison with the neo XY1. In the first place it has an additional C-positive block located distally in the neo Y. Additionally there is also a novel C-block in the proximal half of the XR limb of the neo X. The neo XY2 system thus provides the first unambiguous example of the "secondary heterochromatinization" of a sex chromosome system within a single species.