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J. Delaunay - One of the best experts on this subject based on the ideXlab platform.

  • A variant of spectrin low-expression allele αLELYcarrying a Hereditary Elliptocytosis mutation in codon 28
    British journal of haematology, 1994
    Co-Authors: J. Randon, J Maréchal, Didier Dhermy, M. Garbarz, L Boulanger, A. Vallier, Leticia Ribeiro, Gabriel Tamagnini, J. Delaunay
    Abstract:

    Allele alpha LELY is a low-expression allele of the erythroid spectrin alpha-gene. It carries mutations in exon 40 (alpha V/41 polymorphism) and intron 45, respectively, and is associated with partial skipping of exon 46. The latter phenomenon is thought to impair the recruitment of alpha-chains by beta-chains, and would eventually account for the low-expression character. When it occurs in trans to an alpha-allele responsible for Hereditary Elliptocytosis (alpha HE allele; alpha HE/alpha LELY diplotype), allele alpha LELY enhances the severity of Elliptocytosis. Because allele alpha LELY is widespread, we anticipated that it would occasionally carry HE determinants. These variants of allele alpha LELY will be designated alpha HE-LELY allele. The HE component was the known alpha 28 Arg-->His mutation. This alpha HE-LELY allele was investigated within the alpha HE-LELY/alpha LELY diplotype, a diplotype not described before. Except for the neonatal period, the presentation was mild. In a consistent manner, the alpha LELY component in cis of the alpha HE mutation counteracted the like component in trans.

  • diffusion of a particular 4 1 Hereditary Elliptocytosis allele in the french northern alps
    Journal of Biosocial Science, 1993
    Co-Authors: G. Brunet, J. Delaunay, M T Ducluzeau, L Roda, P. Lefrancois, F. Baklouti, J. M. Robert
    Abstract:

    Heterozygous 4.1(-) Hereditary Elliptocytosis results from the absence of one haploid set of protein 4.1, a major component of the red cell skeleton. Two successive epidemiological investigations revealed fifteen probands in the French Northern Alps. The frequency of this disease seems to be very high in four small villages isolated in the Aravis mountains. The genealogical study shows that eleven probands share common ancestors who lived eight or ten generations ago in these villages. Thus there was probably a founder effect from one pair of ancestors, strengthened by endogamy. In contrast, four probands originate from another area and are not genealogically related. Recent results in molecular genetics support the present data.

  • an spectrin mutation responsible for Hereditary Elliptocytosis associated in cis with the v 41 polymorphism
    Human Genetics, 1993
    Co-Authors: Dalla N Venezia, L Morlé, N. Alloisio, Didier Dhermy, M. Garbarz, R Wilmotte, A Forissier, Nathalie Parquet, T Rousset, J. Delaunay
    Abstract:

    The α207 Leu→Pro mutation in spectrin has recently been identified as a cause of αI/50-46a Hereditary Elliptocytosis (HE) or pyropoikilocytosis among Black people. We have found this mutation in a Moroccan family in both the heterozygous and homozygous states. The mutated α-spectrin allele carried, in cis, the αV/41 polymorphism, a common polymorphism altering the peptide maps and associated with a low-expression level. This is the first report of the cis combination of an HE mutation and the αV/41 polymorphism. Presumably, such a combination accounts for the very low expression of the abnormal allele in the heterozygous state.

  • An α-spectrin mutation responsible for Hereditary Elliptocytosis associated in cis with the α^V/41 polymorphism
    Human Genetics, 1993
    Co-Authors: N. Dalla Venezia, N Alloisio, L Morlé, M. Garbarz, R Wilmotte, A Forissier, Nathalie Parquet, T Rousset, D Dhermy, J. Delaunay
    Abstract:

    The α207 Leu→Pro mutation in spectrin has recently been identified as a cause of α^I/50-46a Hereditary Elliptocytosis (HE) or pyropoikilocytosis among Black people. We have found this mutation in a Moroccan family in both the heterozygous and homozygous states. The mutated α-spectrin allele carried, in cis , the α^V/41 polymorphism, a common polymorphism altering the peptide maps and associated with a low-expression level. This is the first report of the cis combination of an HE mutation and the α^V/41 polymorphism. Presumably, such a combination accounts for the very low expression of the abnormal allele in the heterozygous state.

  • Diffusion of a particular 4.1(−) Hereditary Elliptocytosis allele in the French northern Alps
    Journal of biosocial science, 1993
    Co-Authors: G. Brunet, J. Delaunay, M T Ducluzeau, L Roda, P. Lefrancois, F. Baklouti, J. M. Robert
    Abstract:

    Heterozygous 4.1(-) Hereditary Elliptocytosis results from the absence of one haploid set of protein 4.1, a major component of the red cell skeleton. Two successive epidemiological investigations revealed fifteen probands in the French Northern Alps. The frequency of this disease seems to be very high in four small villages isolated in the Aravis mountains. The genealogical study shows that eleven probands share common ancestors who lived eight or ten generations ago in these villages. Thus there was probably a founder effect from one pair of ancestors, strengthened by endogamy. In contrast, four probands originate from another area and are not genealogically related. Recent results in molecular genetics support the present data.

C. Brancati - One of the best experts on this subject based on the ideXlab platform.

  • Spectrin Cosenza: a novel β chain variant associated with Sp αI/74 Hereditary Elliptocytosis
    British journal of haematology, 1997
    Co-Authors: Antonio Qualtieri, Angela Aurora Pasqua, M. G. Bisconte, M. Le Pera, C. Brancati
    Abstract:

    A Calabrian family (Southern Italy) with Sp alpha(I/74) Hereditary Elliptocytosis (HE) in the heterozygous state was studied. Sp alpha(I/74) HE is associated with asymptomatic Elliptocytosis, a defect in spectrin dimer self association and an increase of the alpha(I/74) kD fragment from the alpha chain after partial tryptic digestion of spectrin. To identify the underlying molecular defect, we analysed exons V, W, X, Y, Z of the beta gene and exon 2 of the alpha gene by single-strand conformational polymorphism (SSCP) of the amplification products. Direct DNA sequencing of the mutant exon showed a C-->G substitution at position 6284 of the beta gene. The corresponding substitution at the protein level was Arg-->Pro in the 2064 position of the beta-spectrin chain.

  • SpαI/65 Hereditary Elliptocytosis in Calabria (southern Italy)
    Human genetics, 1995
    Co-Authors: Antonio Qualtieri, Angela Aurora Pasqua, M. G. Bisconte, M. Bria, C. Brancati
    Abstract:

    The αI/65 variant of spectrin has been described in black people, in North Africans and recently in two southern Italian families. This variant is associated in the heterozygous state with mild Hereditary Elliptocytosis (HE) and the molecular basis of the defect is invariably the duplication of TTG at codon 154 of the α spectrin gene. The present study reports the identification of five Calabrian families with SPαI/65 HE and their distribution in the population.

R Wilmotte - One of the best experts on this subject based on the ideXlab platform.

  • Hereditary Elliptocytosis associated with spectrin le puy in a japanese family ultrastructural aspect of the red cell skeleton
    European Journal of Haematology, 2009
    Co-Authors: J Maréchal, R Wilmotte, Hideho Wada, Trigona Koffa, Akio Kanzaki, Kimiko Ikoma, Ayumi Yawata, Takafumi Inoue, Kaoru Takanashi, Akira B Miura
    Abstract:

    A dominantly-inherited Hereditary Elliptocytosis of intermediate severity was recorded in a Japanese family from Yamagata. The condition was associated with a spectrin truncated beta-chain (MW: 214 kD; 31% of total beta-spectrin), and a defect of mutant spectrin as regards tetramerization and phosphorylation. cDNA analysis revealed skipping of exon X, the third-to-last exon of the spectrin beta-gene. At the gene level, a one-base substitution (A-->G) changed position +4 of the 5' donor splice site consensus sequence of intron X. This mutation has been described before in a French kindred, defining spectrin Le Puy. Electron micrographs following quick-freeze deep-etching showed that the skeletal network was disorganized.

  • an spectrin mutation responsible for Hereditary Elliptocytosis associated in cis with the v 41 polymorphism
    Human Genetics, 1993
    Co-Authors: Dalla N Venezia, L Morlé, N. Alloisio, Didier Dhermy, M. Garbarz, R Wilmotte, A Forissier, Nathalie Parquet, T Rousset, J. Delaunay
    Abstract:

    The α207 Leu→Pro mutation in spectrin has recently been identified as a cause of αI/50-46a Hereditary Elliptocytosis (HE) or pyropoikilocytosis among Black people. We have found this mutation in a Moroccan family in both the heterozygous and homozygous states. The mutated α-spectrin allele carried, in cis, the αV/41 polymorphism, a common polymorphism altering the peptide maps and associated with a low-expression level. This is the first report of the cis combination of an HE mutation and the αV/41 polymorphism. Presumably, such a combination accounts for the very low expression of the abnormal allele in the heterozygous state.

  • An α-spectrin mutation responsible for Hereditary Elliptocytosis associated in cis with the α^V/41 polymorphism
    Human Genetics, 1993
    Co-Authors: N. Dalla Venezia, N Alloisio, L Morlé, M. Garbarz, R Wilmotte, A Forissier, Nathalie Parquet, T Rousset, D Dhermy, J. Delaunay
    Abstract:

    The α207 Leu→Pro mutation in spectrin has recently been identified as a cause of α^I/50-46a Hereditary Elliptocytosis (HE) or pyropoikilocytosis among Black people. We have found this mutation in a Moroccan family in both the heterozygous and homozygous states. The mutated α-spectrin allele carried, in cis , the α^V/41 polymorphism, a common polymorphism altering the peptide maps and associated with a low-expression level. This is the first report of the cis combination of an HE mutation and the α^V/41 polymorphism. Presumably, such a combination accounts for the very low expression of the abnormal allele in the heterozygous state.

  • alpha i 65 Hereditary Elliptocytosis in southern italy evidence for an african origin
    Human Genetics, 1992
    Co-Authors: Miraglia E Del Giudice, J. Delaunay, N. Alloisio, R Wilmotte, Silverio Perrotta, M T Ducluze, S Cutillo, Achille Iolascon
    Abstract:

    αI/65 Hereditary Elliptocytosis (HE) is due to the duplication of TTG codon 1541 (leucine) of α-spectrin and is associated with a constant haplotype. It was encountered exclusively in African and American Blacks, and in North Africans. We assumed that it diffused from the Benin-Togo area to Northern Africa. We now report two South Italian families with αI/65 HE. The phenotype fully conformed to previous descriptions. The mode of transmission was dominant; however, the manifestations were more pronounced when the common, low expression level αV/41 allele occurred in trans to the αI/65 allele, also conforming to previous records. The mutation underlying αI/65 HE turned out to be, again, the duplication of TTG codon 154 and the associated haplotype was the same as that encountered previously (+-+; XbaI, PvuII, MspI). Thus, the αI/65 allele found in Italy must have been introduced from North Africa across the Sicilian channel and would ultimately have originated from the Benin-Togo area. It would witness the same migratory stream as that followed by the Benin type haemoglobin S allele, which is also present in Southern Italy.

Didier Dhermy - One of the best experts on this subject based on the ideXlab platform.

  • Coinheritance of α- and β-Spectrin Gene Mutations in a Case of Hereditary Elliptocytosis
    Blood, 1998
    Co-Authors: Didier Dhermy, Odile Bournier, Colette Galand, May-jean King, Thérèse Cynober, Irene Roberts, Frederick Kanyike, Adekunle Adekile
    Abstract:

    To the Editor: Many mutations in the α- and β-spectrin genes are known to be associated with Hereditary Elliptocytosis (HE). Spectrin abnormalities are detected as abnormal peptides after limited trypsin digestion of spectrin (Sp).[1][1] We had an opportunity to study a Filipino family living in

  • red blood cell abnormalities in Hereditary Elliptocytosis and their relevance to variable clinical expression
    American Journal of Clinical Pathology, 1997
    Co-Authors: Paolo Silveira, Narla Mohandas, Didier Dhermy, Thérèse Cynober, Gil Tchernia
    Abstract:

    Marked variations are seen in the clinical manifestations of Hereditary Elliptocytosis (HE). To define the cellular alteration(s) that best reflect the variable expression of the disease, we evaluated the pathobiologic features of red blood cells in a series of 18 patients with HE, 15 persons from six families with HE as a result of defects in spectrin, and 3 persons from one family with HE caused by partial or total deficiency of protein 4.1. We found that decreased cellular deformability is a distinguishing feature of red blood cells in all patients studied. Comparison of volume and hemoglobin content histograms of red blood cells and reticulocytes revealed that cell fragmentation is a feature of mature red blood cells. The extent of red blood cell fragmentation as reflected by increased percentage of microcytic red blood cells was the best indicator of the severity of hemolytic anemia. Furthermore, we found that the observed variations in cellular properties of HE red blood cells in different persons is the consequence of varying amounts of mutant protein assembled into the membrane. These findings enabled us to define the mechanistic basis for cellular changes in this red blood cell membrane disorder better and also to obtain insight into the cellular basis for variable clinical expression.

  • A variant of spectrin low-expression allele αLELYcarrying a Hereditary Elliptocytosis mutation in codon 28
    British journal of haematology, 1994
    Co-Authors: J. Randon, J Maréchal, Didier Dhermy, M. Garbarz, L Boulanger, A. Vallier, Leticia Ribeiro, Gabriel Tamagnini, J. Delaunay
    Abstract:

    Allele alpha LELY is a low-expression allele of the erythroid spectrin alpha-gene. It carries mutations in exon 40 (alpha V/41 polymorphism) and intron 45, respectively, and is associated with partial skipping of exon 46. The latter phenomenon is thought to impair the recruitment of alpha-chains by beta-chains, and would eventually account for the low-expression character. When it occurs in trans to an alpha-allele responsible for Hereditary Elliptocytosis (alpha HE allele; alpha HE/alpha LELY diplotype), allele alpha LELY enhances the severity of Elliptocytosis. Because allele alpha LELY is widespread, we anticipated that it would occasionally carry HE determinants. These variants of allele alpha LELY will be designated alpha HE-LELY allele. The HE component was the known alpha 28 Arg-->His mutation. This alpha HE-LELY allele was investigated within the alpha HE-LELY/alpha LELY diplotype, a diplotype not described before. Except for the neonatal period, the presentation was mild. In a consistent manner, the alpha LELY component in cis of the alpha HE mutation counteracted the like component in trans.

  • an spectrin mutation responsible for Hereditary Elliptocytosis associated in cis with the v 41 polymorphism
    Human Genetics, 1993
    Co-Authors: Dalla N Venezia, L Morlé, N. Alloisio, Didier Dhermy, M. Garbarz, R Wilmotte, A Forissier, Nathalie Parquet, T Rousset, J. Delaunay
    Abstract:

    The α207 Leu→Pro mutation in spectrin has recently been identified as a cause of αI/50-46a Hereditary Elliptocytosis (HE) or pyropoikilocytosis among Black people. We have found this mutation in a Moroccan family in both the heterozygous and homozygous states. The mutated α-spectrin allele carried, in cis, the αV/41 polymorphism, a common polymorphism altering the peptide maps and associated with a low-expression level. This is the first report of the cis combination of an HE mutation and the αV/41 polymorphism. Presumably, such a combination accounts for the very low expression of the abnormal allele in the heterozygous state.

N. Alloisio - One of the best experts on this subject based on the ideXlab platform.

  • spectrin mutations in Hereditary Elliptocytosis and Hereditary spherocytosis
    Human Mutation, 1996
    Co-Authors: Philippe Maillet, L Morlé, N. Alloisio, Jean Delaunay
    Abstract:

    Hereditary Elliptocytosis (HE), its aggravated form Hereditary pyropoikilocytosis (HPP), and Hereditary spherocytosis (HS) designate a set of congenital hemolytic syndromes. The responsible mutations lie in several genes encoding proteins of the red cell membrane. In particular, they involve the SPTA1 and SPTB genes that encode erythroid spectrin alpha- and beta-chains, respectively. In situ, spectrin is a alpha 2 beta 2 fibrillar tetramer resulting from the head-to-head self-association of two alpha beta dimers. In HE, the 24 known alpha-chain mutations lie in the self-association site or its vicinity, whereas the 17 beta-chain mutations occur in the self-association site itself (record of November 30, 1995). Allele alpha LELY (LELY: Low Expression LYon) is found in ethnic groups remote from one another with a uniform frequency (20-30% of all alpha-alleles). It allows an expanded expression of any HE alpha-allele located in trans and results in severe HE or in HPP. In HS, a number of spectrin mutations have been recorded recently. Allele alpha LEPRA (LEPRA: Low Expression PRAgue) would occur in a recurrent fashion.

  • an spectrin mutation responsible for Hereditary Elliptocytosis associated in cis with the v 41 polymorphism
    Human Genetics, 1993
    Co-Authors: Dalla N Venezia, L Morlé, N. Alloisio, Didier Dhermy, M. Garbarz, R Wilmotte, A Forissier, Nathalie Parquet, T Rousset, J. Delaunay
    Abstract:

    The α207 Leu→Pro mutation in spectrin has recently been identified as a cause of αI/50-46a Hereditary Elliptocytosis (HE) or pyropoikilocytosis among Black people. We have found this mutation in a Moroccan family in both the heterozygous and homozygous states. The mutated α-spectrin allele carried, in cis, the αV/41 polymorphism, a common polymorphism altering the peptide maps and associated with a low-expression level. This is the first report of the cis combination of an HE mutation and the αV/41 polymorphism. Presumably, such a combination accounts for the very low expression of the abnormal allele in the heterozygous state.

  • alpha i 65 Hereditary Elliptocytosis in southern italy evidence for an african origin
    Human Genetics, 1992
    Co-Authors: Miraglia E Del Giudice, J. Delaunay, N. Alloisio, R Wilmotte, Silverio Perrotta, M T Ducluze, S Cutillo, Achille Iolascon
    Abstract:

    αI/65 Hereditary Elliptocytosis (HE) is due to the duplication of TTG codon 1541 (leucine) of α-spectrin and is associated with a constant haplotype. It was encountered exclusively in African and American Blacks, and in North Africans. We assumed that it diffused from the Benin-Togo area to Northern Africa. We now report two South Italian families with αI/65 HE. The phenotype fully conformed to previous descriptions. The mode of transmission was dominant; however, the manifestations were more pronounced when the common, low expression level αV/41 allele occurred in trans to the αI/65 allele, also conforming to previous records. The mutation underlying αI/65 HE turned out to be, again, the duplication of TTG codon 154 and the associated haplotype was the same as that encountered previously (+-+; XbaI, PvuII, MspI). Thus, the αI/65 allele found in Italy must have been introduced from North Africa across the Sicilian channel and would ultimately have originated from the Benin-Togo area. It would witness the same migratory stream as that followed by the Benin type haemoglobin S allele, which is also present in Southern Italy.