Search PubMed⌕ Search

Biomedical subjects

M Baiget

Publications and source records attributed to M Baiget.

At least 163 records · Page 9Linked to original sources

Hb F-Catalonia or alpha 2G gamma(2)15(A12)Trp----Arg.

Hb F-Catalonia, a G gamma chain variant with a Trp----Arg substitution at position gamma 15(A12), was observed in two Spanish newborn babies from Northeastern Spain. Analyses were performed with different reversed phase high performance liquid chromatographic procedures that allowed the identification of the amino acid replacement in only a minute quantity of the isolated G gamma X chain.

Amino Acids↗

[Genetic analysis of Spanish families with myotonic dystrophy].

Myotonic dystrophy (MD) is the most common form of muscular dystrophy in adult life, with a clinical prevalence of 5.5/100,000, being the gene prevalence of 13.5. The disease is autosomal dominant with variable expressivity, existing a congenital form with a severe prognosis. Recent genetic studies revealed that the DM gene is localized in the chromosome's 19 proximal long arm and with recombinant DNA techniques, several polymorphic markers have been isolated near the gene, the closet being Apo-CII, LDR 152 and p 4.1. We have studied clinically, electrophysiologically and by genetic analysis 6 families with 32 individuals. We have diagnosed the disease in 16 individuals and after the molecular analysis, the DM gene was totally excluded in 6 clinically healthy individuals. In our preliminary study, the use of Msp I/p 4.1, Bgl II/LDR 152 y Ban I, Bgl I, Taq I/Apo-CII c-DNA and genomic was found the most informative combination. These molecular analysis seem to be very useful as a complement to the diagnosis of myotonic dystrophy.

Adolescent↗

[DNA polymorphisms as implant markers in allogeneic bone marrow transplantation. Preliminary evaluation].

After allogeneic bone marrow transplantation (BMT), patient hematopoietic and lymphoid cells are replaced by cells derived from the donor marrow. To document and characterize successful engraftment, host and donor cells must be distinguished from each other. We have used DNA sequence polymorphism analysis in 6 patients, at times varying, to determine reliably the host or donor origin of posttransplant cell populations and to compare these results with those obtained using red blood cell antigens and cytogenetics. Initially full engraftment was documented in all patients. In 1 patient a mixed lymphohematopoietic chimerism was documented 6 months after BMT and it reverted to donor hematopoiesis at 1 year post BMT. Posttransplant leukemic relapse was studied in two patients and shown to be of host origin in both cases. The DNA restriction fragment length polymorphisms (RFLP), are a powerful tool for the documentation of engraftment after BMT, to document mixed lymphohematopoietic chimerism and for the evaluation of leukemic relapse.

Biomarkers↗

[Detection of carriers and prenatal diagnosis of cystic fibrosis in Spanish families using DNA markers].

A molecular study of 36 Spanish families with cystic fibrosis (CF) patients is reported. The analysis of seven DNA polymorphisms adjacent to the CF gene permitted the diagnosis of 95% of the probable carriers and the antenatal diagnosis in the seven cases in which it was requested. The application of recombinant DNA techniques to the study of CF by means of the analysis of DNA markers linked to the CF gene is useful, not only to identify the latter, but also as a reference to investigate its molecular pathology and for diagnostic purposes in high risk families (families with involved members).

Cystic Fibrosis↗

[Use of the recombinant DNA technic in studying cystic fibrosis in 14 Spanish families: detection of carriers and healthy subjects].

Fourteen Spanish families, containing at least one affected child with cystic fibrosis, were typed for restriction fragment length polymorphisms (RFLPs) by proper pJ3.11, pmet H and pmet D. Nine (64.3%) were fully informative for prenatal diagnosis and carrier detection; four (28.5%) were partially informative and prenatal exclusion of an affected fetus could be carried out in half of pregnancies. One (7.1%) was uninformative for these probes. Allelic frequencies obtained have also been analized, being pJ3.11 probe the most informative in our families.

Alleles↗

[Prenatal diagnosis in a family carrying the fragile X syndrome using recombinant DNA technics].

The prenatal diagnosis in a family carrying the Fragile Chromosome X Syndrome (sex linked mental retardation) has been performed using Recombinant DNA techniques. The use of these techniques together with cytogenetics and prenatal diagnosis using chorial biopsy, have enabled the diagnosis of the disease on a male foetus on the twelfth week of pregnancy. Similarly, we have been able to confirm the carrier state of the mother (proven) and the grand mother, and furthermore, the non affected condition of an older son to this mother. The results obtained reveal the importance of the new molecular techniques applied to the diagnosis of certain diseases with a genetic origin.

Adult↗

[Use of dystrophin c-DNA for the direct diagnosis of Duchenne muscular dystrophy in female carriers].

DNA polymorphisms have been widely used as genetic markers for identification of the X chromosome that carries the mutation for Duchenne Muscular Dystrophy (DMD) in affected families, but serious limitations are associated with this approach. The complementary DNA (c-ADN) of the DMD gene has recently been isolated and shown to detect partial gene deletions in a large proportion of patients. We present the study of five DMD families in which we have shown the existence of a partial deletion in the DMD gene in the affected boys. We have evaluated the usefulness of this direct approach to diagnose DMD carriers in these families using the c-DNA derived probes. In all cases we have obtained satisfactory results. The method seems to be more reliable, more rapid and less expensive than linkage studies with DNA polymorphisms.

Chromosome Deletion↗

Determination of the spectrum of beta-thalassemia genes in Spain by use of dot-blot analysis of amplified beta-globin DNA.

We have delineated the molecular lesions causing beta-thalassemia in Spain, a country that has witnessed the passage of different Mediterranean populations over the centuries, in order to evaluate the extent of heterogeneity of these mutations and to make possible simplified prenatal diagnosis of the disorder in that country. The use of the polymerase chain-reaction (PCR) technique to preferentially amplify beta-globin DNA sequences that contain the most frequent beta-thalassemia mutations in Mediterraneans enabled us to rapidly analyze 58 beta-thalassemia alleles in a dot-blot format either by hybridization with allele-specific radiolabeled oligonucleotide probes or by direct sequence analysis of the amplification product. The Spanish population carries seven different beta-thalassemia mutations; the nonsense codon 39 is predominant (64%), whereas the IVS1 position 110 mutation, the most common cause of beta-thalassemia in the eastern part of the Mediterranean basin, is underrepresented (8.5%). The IVS1 mutation at position 6 accounts for 15% of the defects and leads to a more severe form of beta+-thalassemia than originally described in most of the patients we studied. In this study, we demonstrate further the usefulness of the dot-blot hybridization of PCR-amplified genomic DNA in both rapid population surveys and prenatal diagnosis of beta-thalassemia.

Base Sequence↗

Patterns of polymorphism and linkage disequilibrium for cystic fibrosis.

Four polymorphic markers that map within 80 kb of an HTF island which is genetically very close to the cystic fibrosis locus have been identified. We have analyzed the linkage disequilibrium between each of these markers and the cystic fibrosis mutation in 89 families from four European countries, Denmark, Finland, Spain, and Great Britain. Strong linkage disequilibrium between three polymorphic sites and cystic fibrosis was observed. The markers on the J3.11 (D7S8) side of the HTF island show stronger disequilibrium than those on the met side. Linkage disequilibrium between markers and disease alters the probability that a person of a given haplotype is a carrier in some populations and helps to identify regions of a sequence that are most likely to contain the cystic fibrosis mutation.

Chromosome Mapping↗

The 3' ends of the deletions of Spanish delta beta zero-thalassemia and black HPFH 1 and 2 lie within 17 kilobases.

Spanish delta beta zero-thalassemia, a mild thalassemic condition characterized by increased level of hemoglobin (Hb) F production during adult life, is known to be due to a large deletion starting within the beta globin gene cluster and extending beyond the 3' breakpoint of any other similar deletional defects so far identified. By molecular cloning and by genomic mapping we now demonstrate that the deletion of Spanish delta beta zero-thalassemia ends at approximately 11 and 17 kilobases (kb) downstream to the 3' endpoints of black hereditary persistence of fetal hemoglobin (HPFH) type 1 and 2, respectively. As suggested by the complete characterization of this and other deletional defects involving the beta globin gene cluster, the 5' and 3' breakpoints of several deletions cluster in rather restricted DNA areas, further strengthening the idea that common molecular mechanisms may operate in causing these deletions.

Base Sequence↗

A case of hemoglobin Indianapolis [beta 112(G14) Cys----Arg] in an individual from Cordoba, Spain.

Hemoglobin Indianapolis was first described by Adams et al (1,2) as a very unstable variant with a phenotype similar to severe beta-thalassemia. We have also characterized this variant, but there are several differences in the clinical expression of the variant described in our report and those described in the original case. We found Hb Indianapolis to be unstable, but not to the extent that it could not be detected by routine testing. The four family members heterozygous for the variant were not anemic, showed normal hematologic values, and did not exhibit any severe clinical disadvantages, although there was slight reticulocytosis. The variant could not be resolved from Hb A on cellulose acetate (pH 8.4), but isoelectric focusing showed a double band in the region of Hb A that is probably the variant and Hb A. However, the variant chain was clearly evident by globin chain analyses in acid and alkaline buffers. The condition of additional blood samples did not allow us to determine the oxygen dissociation properties of the variant or the rates of globin chain synthesis.

Adult↗