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D Grinberg

Publications and source records attributed to D Grinberg.

At least 37 records · Page 2Linked to original sources
PubMed1997

Putative association of a mutant ROM1 allele with retinitis pigmentosa.

Retinitis pigmentosa (RP) is a clinically and genetically heterogeneous form of retinal degeneration. Several genes and loci have been shown to be involved in the disease, although each of them only accounts for a few cases. Mutations in the gene encoding ROM1, a rod-specific protein, have been putatively associated with several forms of RP. Here we describe a double-mutant allele of this gene, P60T and T108M, present in two affected sibs and also in two healthy members of a Spanish RP family. The same double-mutant allele was previously considered to be responsible for autosomal dominant RP in one family. We now report data that question the potential pathogenicity of these two ROM1 mutations.

Adolescent↗
PubMed1997

Genetic fine localization of the beta-glucocerebrosidase (GBA) and prosaposin (PSAP) genes: implications for Gaucher disease.

Mutations in the glucocerebrosidase (GBA) and prosaposin (PSAP) genes are responsible for Gaucher disease, the most prevalent sphingolipidosis. Somatic cell hybrid analysis and in situ hybridization experiments have localized the GBA gene to 1q21 and the PSAP gene to 10q21-q22. We performed pairwise and multi-point linkage analyses between the two genes and several highly polymorphic markers from the Généthon human linkage map. Our results show that six markers cosegregate with the GBA gene (Zmax = 8.73 at theta = 0.00 for marker D1S2714) and define a 3.2-cM interval between D1S305 and D1S2624 as the most probable location for the gene. Three of these markers (D1S2777, D1S303, and D1S2140), as well as the gene encoding pyruvate kinase (PKLR), are contained in a single YAC clone together with the GBA gene. A new polymorphism was identified within the PSAP gene (C16045T) and used for linkage studies. The multi-point analysis places the gene in a 9.8-cM interval between D10S1688 and D10S607. The fine localization of these genes provides a useful tool for cosegregation analysis, indirect molecular diagnosis, and population genetic studies.

Chromosome Mapping↗
PubMed1996

A novel mutation in exon 17 of the beta-subunit of rod phosphodiesterase in two RP sisters of a consanguineous family.

We report the molecular analysis of the beta subunit of the rod phosphodiesterase (PDEB) gene in a consanguineous autosomal recessive retinitis pigmentosa family that shows homozygosity for polymorphisms in the genomic region comprising this gene, and positive linkage between a PDEB marker and the disease. The two affected sisters are homozygous for a T to G transversion in codon 699 of the PDEB gene, leading to the substitution of a leucine by an arginine residue. This change, enclosed in the catalytic domain of the PDEB, could result in a modification of the protein structure preventing the physiological hydrolysis of cGMP.

3',5'-Cyclic-GMP Phosphodiesterases↗
PubMed1996

Autosomal recessive retinitis pigmentosa in Spain: evaluation of four genes and two loci involved in the disease.

Autosomal recessive retinitis pigmentosa (ARRP) is a genetically heterogeneous form of retinal degeneration. The genes for the beta-subunit of rod phosphodiesterase (PDEB), rhodopsin (RHO), peripherin/RDS (RDS) and the rod outer segment membrane protein 1 (ROM1), as well as loci at 6p and 1q, have previously been reported as the cause of ARRP. In order to determine whether they are responsible for the disease in Spanish pedigrees, linkage and homozygosity studies using markers at these loci were carried out on 47 Spanish ARRP families. SSCP analysis was performed to search for mutations in the genes cosegregating with the disease in particular pedigrees. Three homozygous mutations in the PDEB gene were found, thus accounting for 6% of the cases. No other disease-causing mutation was observed in the other genes analysed, nor was significant evidence found for the involvement of the loci at 6p or 1q. On the basis of these data, it is unlikely that these genes and loci account for a considerable proportion of ARRP cases.

Calcium-Binding Proteins↗
PubMed1995

Homozygous tandem duplication within the gene encoding the beta-subunit of rod phosphodiesterase as a cause for autosomal recessive retinitis pigmentosa.

Autosomal recessive retinitis pigmentosa (ARRP) is a degenerative disease of photoreceptors in which defects in the rhodopsin and phosphodiesterase beta-subunit (PDEB) loci have been reported. To assess the involvement of PDEB in ARRP families from Spain, we screened a panel of 19 families for linkage to markers within or close to the PDEB gene. Homozygosity was also tested in cases of consanguinity. This combined approach ruled out PDEB as the cause of the disease in all but one of the families. Molecular characterization of the gene in that family (a consanguineous pedigree) revealed a homozygous 71-bp tandem duplication in exon 1 of the affected member, the parents being heterozygous. This defect causes a frameshift mutation which leads to a premature stop codon, suggesting that this mutant allele is the underlying cause of ARRP in this patient. According to the data presented here, the PDEB gene is not the main gene responsible for ARRP, but accounts for about 5% of the cases.

Base Sequence↗
PubMed1995

Gaucher disease in Spanish patients: analysis of eight mutations.

Gaucher disease is particularly prevalent among Ashkenazi Jews; thus most studies have been reported on this ethnic group. We present the first data on Spanish patients with Gaucher disease and provide one of the first reports on a fairly well defined, large, non-Jewish population. Eight mutations were analyzed in 35 patients, with different clinical subtypes, by restriction enzyme digestion or allele-specific oligonucleotide (ASO) hybridization, after PCR amplification of genomic DNA. Analysis of the eight mutations allowed identification of 77.2% of the disease alleles, N370S and L444P alone accounting for 70%. Mutation N370S, carried by 31 alleles (44.3%), appeared to be the most prevalent in the Spanish population. The frequency of this mutation and of the N370S/N370S genotype is closer to those described for Ashkenazi Jews than to the frequencies found in other non-Jewish populations. Mutation L444P, the second most abundant mutation, occurred in 25.7% of the disease alleles. Four alleles carrying mutation D409H (5.7%) were detected in patients of different clinical expression and one RecNciI allele in a type I patient. Mutations 84GG, IVS2 + 1, R463C, and RecTL were also screened but were not found in any of our patients.

Adolescent↗
PubMed1995

Evidence against involvement of recoverin in autosomal recessive retinitis pigmentosa in 42 Spanish families.

Autosomal recessive retinitis pigmentosa (ARRP) is a degenerative disease of photoreceptors in which defects in the genes encoding rhodopsin, the beta subunit of rod phosphodiesterase (PDEB) and, recently, in the gene for rod cGMP-gated channel, have been reported. However, detailed genetic involvement has not been ascertained in the great majority of cases. Recoverin, another member of the light transduction pathway, is a candidate gene for ARRP. We report the first analyses of the involvement of the recoverin gene (RCV1) in 42 Spanish ARRP families. Linkage and homozygosity studies with an intragenic polymorphism and the close markers D17S945 and D17S786 ruled out RCV1 as the cause of ARRP in 38 pedigrees. In the four remaining families, single strand conformation polymorphism analysis of the recoverin-coding region detected no mutations in the parents or in the affected members. These results strongly suggest that mutations in the RCV1 gene are not responsible for ARRP in these families.

Base Sequence↗
PubMed1995

Unusual expression of Gaucher's disease: cardiovascular calcifications in three sibs homozygous for the D409H mutation.

Three sisters suffering from an unusual form of Gaucher's disease are described. These patients had cardiovascular abnormalities consisting of calcification of the ascending aorta and of the aortic and mitral valves. Neurological findings included ophthalmoplegia and saccadic eye movements in two patients, and tonic-clonic seizures in the third. The three patients died, two of them after having undergone aortic valve replacement. Tissue was obtained from one of the sibs and fibroblast and liver beta-glucocerebrosidase activity was reduced to 4% and 11% of mean normal values. Genotype analysis indicated that the patient was homozygous for the D409H mutation. It is tempting to relate the phenotype of severe cardiac involvement to the D409H/D409H genotype, although further cases will be needed before this association can be confirmed.

Adolescent↗
PubMed1994

Genetic fine localization of the arrestin (S-antigen) gene 4 cM distal from D2S172.

Arrestin is a component of the light transduction cascade that takes place in the outer segment of retinal rods. In situ hybridization and linkage analysis have localized the arrestin gene to a region of 50 cM between CRYG alpha and D2S23/D2S55 on chromosome 2q24-37. We have performed pairwise and multipoint linkage analysis between arrestin and four highly polymorphic markers from this region. The results indicate tight linkage between the gene and the microsatellite D2S172 (Zmax = 9.25 at theta = 0.038). This fine localization of the gene should provide a useful tool for cosegregation analyses involving the arrestin gene.

Antigens↗
PubMed1993

Identification of positive and negative regulatory elements involved in the retinoic acid/cAMP induction of Fgf-3 transcription in F9 cells.

The proto-oncogene Fgf-3 has been implicated as an important signalling molecule in vertebrate development. In the mouse, it is expressed for a limited time at a multitude of sites from embryonic day 7 to birth. Transcription of Fgf-3 initiates at three promoter regions resulting in the generation of various mRNAs which nevertheless all encode the same protein products. A 1.7kb DNA fragment which encompasses these regions was joined to the CAT reporter gene and shown to function as a promoter in embryonal carcinoma cells. In stable transfectants the promoter retains its retinoic acid inducibility, initiating transcription at the same cap-sites as the endogenous gene. In differentiated F9 cells, transient transfection of progressive and targeted deletion mutants of the promoter region has revealed at least two positive and three negative regulatory elements. With one exception, loss of these elements was shown to dramatically affect promoter activity in stable transfectants of F9 cells. However the promoter remained inducible by retinoic acid to differing degrees, apart from deletions encompassing PS-4A which essentially abolished promoter activity in both undifferentiated and differentiated cells. The sequences of these potential regulatory regions were further defined using DNase-I footprinting, revealing some similarities to consensus binding sites for known transcription factors.

Animals↗
PubMed1993

Frequency of the arylsulphatase A pseudodeficiency allele in the Spanish population.

Pseudodeficiency in arylsulphatase A (ASA) is a relatively frequent condition in healthy individuals. It produces a reduction in enzyme activity similar to that found in metachromatic leukodystrophy (MLD). Unambiguous discrimination between the two conditions cannot be achieved through conventional enzyme activity assays. A PCR method has been developed which detects the pseudodeficiency (pd) allele using a single pair of primers encompassing the mutation site and hair follicles as the source of DNA. The frequency of this allele in the Spanish population has been evaluated and correlations between different genotypes and ASA activity levels have been established. Ten out of 55 individuals were heterozygous for the ASA pd allele, while two were homozygous. The allele frequency was thus 12.7%.

Alleles↗
PubMed1993

[Enteropathogenic microorganisms in children with acute diarrhea in 2 hospitals of Rosario, Argentina].

As part of a multicenter collaborative study the relative frequency of enteropathogenic agents in children less than 5 years of age with acute diarrhea was determined. Rates of isolation were similar as regards sex, age, and season. The frequency of polymorphonuclear cells (PMN) in the stools was significantly higher among patients requiring admission in comparison with ambulatory patients. Enteropathogenic E. coli (EPEC) was isolated more frequently in that group in comparison with outpatients (p < 0.001), mainly among children less than 5 months of age. The most prevalent agents were EPEC (26.1%), enterotoxigenic E. coli (ETEC) (9.7%), Shigella (8.5%), Rotavirus (5.1%), Giardia (3.6%), Campylobacter (3.2%), and Salmonella (2.4%). The EPEC predominant serogroups were 0 111, 0 55, 0 26, and 0 119. ETEC serotypes 0 153:H45 and 0 128:H21 were more often isolated. The predominant species in the genus Shigella were S. flexneri (80.5%), and S. sonnei (9.5%); in the genus Campylobacter, the species were C. jejuni (81.3%), and C. coli (18.7%). Shigella was clearly related to the presence of PMN in the faeces, in children less than 5 months old. Campylobacter was more frequent in ambulatory patients more than one year of age. Rotavirus was found predominantly in autumn and winter. Salmonella and ETEC were more frequent in summer. Giardia was associated with weight loss. In about 10% of the cases there were simultaneous mixed isolations of two or more agents. Salmonella isolates were sensitive to the majority of antimicrobial agents probed. Many Shigella and E. coli were resistant to sulfamethoxazole-trimethoprim and ampicillin (40-80%). Nearly all enterobacteria were sensitive to gentamicin and norfloxacin.

Acute Disease↗
PubMed1992

Linkage disequilibrium detected between myotonic dystrophy and the anonymous marker D19S63 in the Spanish population.

We used the following polymorphic markers: APOC2 (BanI, BglI, TaqI), CKMM (NcoI, TaqI), and D19S63 (PstI) to haplotype 33 Spanish myotonic dystrophy (DM) families. We analysed the allele and haplotype frequencies of our sample, and the possible association of alleles or haplotypes with the disease. We found a slight linkage disequilibrium between APOC2 (BanI) and DM, but no disequilibrium when using all other APOC2 and CKMM RFLPs; this agrees with data previously reported. In addition, we found a very strong linkage disequilibrium when using D19S63 (PstI), the + allele being associated with the DM locus. This disequilibrium in the Spanish population indicates that D19S63 is very close to the DM locus.

Alleles↗
PubMed1991

Transcriptional regulation of the int-2 gene in embryonal carcinoma cells.

The int-2 gene, which encodes a member of the fibroblast growth factor family, is expressed at specific sites and times during mouse development. In certain embryonal carcinoma cell lines, multiple int-2 transcripts accumulate when the cells are induced to differentiate with retinoic acid and dibutyryl cyclic AMP. Nuclear run-on analyses indicate that the apparent induction of int-2 expression results from an increase in the rate of transcription initiation. Six distinct types of RNA have been delineated, originating from three promoters and terminating at either of two polyadenylation sites. Since each transcript appears to encode the same protein, this complexity may reflect the need for lineage-specific or differentiation-dependent control of expression. By comparing the kinetics of induction and turnover of the different RNA species, we show that the choice of promoter or length of the 3'-untranslated region has no significant effect on the half-lives of the various mRNAs. To further evaluate control at the transcriptional level, we have shown that a 1.7-kilobase fragment of int-2 genomic DNA, when fused to the chloramphenicol acetyltransferase gene, can act as a regulated promoter(s) in differentiated versus undifferentiated embryonal carcinoma cells. This segment of DNA encompasses the three promoter regions previously delineated by RNase mapping plus about 900 base pairs of additional upstream sequences.

Animals↗
PubMedDate not supplied

Midline cleft. Treatment of the bifid nose.

BACKGROUND: Midline facial clefts are rare deformities with a wide range of clinical findings from a simple midline vermillion notch to major skeletal malformations, including orbital hypertelorism. The bifid nose is a relatively uncommon malformation that is frequently associated with hypertelorbitism and midline clefts of the lip. The presentation of a bifid nose ranges from a minimally noticeable midline nasal tip central groove to a complete clefting of the osteocartilaginous framework, resulting in 2 complete half noses. We describe our experience with 2 patients with midface clefts who presented with bifid noses and a variety of other congenital abnormalities. The anatomy, extensive treatment, and complications of the bifid nose are discussed. DESIGN: Retrospective case review and literature review. RESULTS: Successful creation of an aesthetic nasal contour and normal nasal function was achieved without complication via extensive skin, bony, and cartilaginous resection. CONCLUSIONS: The bifid nose challenges the rhinoplasty surgeon. A successful outcome is dependent on a thorough understanding of the bifid nasal anatomy, proper patient evaluation, careful preoperative planning, and meticulous surgical technique.

Adult↗