Genetic and biochemical studies in Argentinean patients with variegate porphyria

Background: A partial deficiency in Protoporphyrinogen oxidase (PPOX) produces the mixed disorder Variegate Porphyria (VP), the second acute porphyria more frequent in Argentina. Identification of patients with an overt VP is absolutely important because treatment depends on an accurate diagnosis bu...

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Autores principales: Rossetti, María Victoria, Granata, Bárbara Xoana, Giudice, Jimena, Parera, Victoria Estela, Batlle, Alcira María del Carmen
Publicado: 2008
Materias:
RNA
Acceso en línea:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_14712350_v9_n_p_Rossetti
http://hdl.handle.net/20.500.12110/paper_14712350_v9_n_p_Rossetti
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id paper:paper_14712350_v9_n_p_Rossetti
record_format dspace
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic adenine
alanine
amino acid
complementary DNA
cytosine
glutamic acid
glycine
guanine
nucleic acid
protoporphyrinogen oxidase
RNA
threonine
thymine
tryptophan
valine
flavoprotein
heme
mitochondrial protein
PPOX protein, human
protoporphyrinogen oxidase
adolescent
adult
amino acid substitution
Argentina
article
binding site
chemical analysis
child
codon
controlled study
DNA flanking region
DNA sequence
exon
family study
female
frameshift mutation
gene amplification
gene deletion
gene insertion
genetic analysis
genetic code
heterozygosity
human
intron
major clinical study
male
missense mutation
molecular biology
mutational analysis
nucleic acid base substitution
nucleotide sequence
porphyria variegata
promoter region
reverse transcription polymerase chain reaction
RNA sequence
RNA transcription
signal transduction
biosynthesis
genetics
heterozygote detection
metabolism
middle aged
polymerase chain reaction
porphyria variegata
Adolescent
Adult
Exons
Female
Flavoproteins
Frameshift Mutation
Heme
Heterozygote Detection
Humans
Male
Middle Aged
Mitochondrial Proteins
Mutation, Missense
Polymerase Chain Reaction
Porphyria, Variegate
Protoporphyrinogen Oxidase
Sequence Analysis, DNA
spellingShingle adenine
alanine
amino acid
complementary DNA
cytosine
glutamic acid
glycine
guanine
nucleic acid
protoporphyrinogen oxidase
RNA
threonine
thymine
tryptophan
valine
flavoprotein
heme
mitochondrial protein
PPOX protein, human
protoporphyrinogen oxidase
adolescent
adult
amino acid substitution
Argentina
article
binding site
chemical analysis
child
codon
controlled study
DNA flanking region
DNA sequence
exon
family study
female
frameshift mutation
gene amplification
gene deletion
gene insertion
genetic analysis
genetic code
heterozygosity
human
intron
major clinical study
male
missense mutation
molecular biology
mutational analysis
nucleic acid base substitution
nucleotide sequence
porphyria variegata
promoter region
reverse transcription polymerase chain reaction
RNA sequence
RNA transcription
signal transduction
biosynthesis
genetics
heterozygote detection
metabolism
middle aged
polymerase chain reaction
porphyria variegata
Adolescent
Adult
Exons
Female
Flavoproteins
Frameshift Mutation
Heme
Heterozygote Detection
Humans
Male
Middle Aged
Mitochondrial Proteins
Mutation, Missense
Polymerase Chain Reaction
Porphyria, Variegate
Protoporphyrinogen Oxidase
Sequence Analysis, DNA
Rossetti, María Victoria
Granata, Bárbara Xoana
Giudice, Jimena
Parera, Victoria Estela
Batlle, Alcira María del Carmen
Genetic and biochemical studies in Argentinean patients with variegate porphyria
topic_facet adenine
alanine
amino acid
complementary DNA
cytosine
glutamic acid
glycine
guanine
nucleic acid
protoporphyrinogen oxidase
RNA
threonine
thymine
tryptophan
valine
flavoprotein
heme
mitochondrial protein
PPOX protein, human
protoporphyrinogen oxidase
adolescent
adult
amino acid substitution
Argentina
article
binding site
chemical analysis
child
codon
controlled study
DNA flanking region
DNA sequence
exon
family study
female
frameshift mutation
gene amplification
gene deletion
gene insertion
genetic analysis
genetic code
heterozygosity
human
intron
major clinical study
male
missense mutation
molecular biology
mutational analysis
nucleic acid base substitution
nucleotide sequence
porphyria variegata
promoter region
reverse transcription polymerase chain reaction
RNA sequence
RNA transcription
signal transduction
biosynthesis
genetics
heterozygote detection
metabolism
middle aged
polymerase chain reaction
porphyria variegata
Adolescent
Adult
Exons
Female
Flavoproteins
Frameshift Mutation
Heme
Heterozygote Detection
Humans
Male
Middle Aged
Mitochondrial Proteins
Mutation, Missense
Polymerase Chain Reaction
Porphyria, Variegate
Protoporphyrinogen Oxidase
Sequence Analysis, DNA
description Background: A partial deficiency in Protoporphyrinogen oxidase (PPOX) produces the mixed disorder Variegate Porphyria (VP), the second acute porphyria more frequent in Argentina. Identification of patients with an overt VP is absolutely important because treatment depends on an accurate diagnosis but more critical is the identification of asymptomatic relatives to avoid acute attacks which may progress to death. Methods: We have studied at molecular level 18 new Argentinean patients biochemically diagnosed as VP. PPOX gene was amplified in one or in twelve PCR reactions. All coding exons, flanking intronic and promoter regions were manual or automatically sequenced. For RT-PCR studies RNA was retrotranscripted, amplified and sequenced. PPOX activity in those families carrying a new and uncharacterized mutation was performed. Results: All affected individuals harboured mutations in heterozygous state. Nine novel mutations and 3 already reported mutations were identified. Six of the novel mutations were single nucleotide substitutions, 2 were small deletions and one a small insertion. Three single nucleotide substitutions and the insertion were at exon-intron boundaries. Two of the single nucleotide substitutions, c.471G>A and c.807G>A and the insertion (c.388+3insT) were close to the splice donor sites in exons 5, 7 and intron 4 respectively. The other single nucleotide substitution was a transversion in the last base of intron 7, g.3912G>C (c.808-1G>C) so altering the consensus acceptor splice site. However, only in the first case the abnormal band showing the skipping of exon 5 was detected. The other single nucleotide substitutions were transversions: c.101A>T, c.995G>C and c.670 T>G that result in p.E34V, p.G332A and W224G aminoacid substitutions in exons 3, 10 and 7 respectively. Activity measurements indicate that these mutations reduced about 50% PPOX activity and also that they co-segregate with this reduced activity value. Two frameshift mutations, c.133delT and c.925delA, were detected in exons 3 and 9 respectively. The first leads to an early termination signal 22 codons downstream (p.S45fsX67) and the second leads to a stop codon 5 codons downstream (p.I309fsX314). One reported mutation was a missense mutation (p.G232R) and 2 were frameshift mutations: c.1082insC and 1043insT. The last mutation was detected in six new apparently unrelated Argentinean families. Conclusion: Molecular analysis in available family members revealed 14 individuals who were silent carriers of VP. Molecular techniques represent the most accurate approach to identify unaffected carriers and to provide accurate genetic counselling for asymptomatic individuals. The initial screening includes the insertion search. © 2008 Rossetti et al; licensee BioMed Central Ltd.
author Rossetti, María Victoria
Granata, Bárbara Xoana
Giudice, Jimena
Parera, Victoria Estela
Batlle, Alcira María del Carmen
author_facet Rossetti, María Victoria
Granata, Bárbara Xoana
Giudice, Jimena
Parera, Victoria Estela
Batlle, Alcira María del Carmen
author_sort Rossetti, María Victoria
title Genetic and biochemical studies in Argentinean patients with variegate porphyria
title_short Genetic and biochemical studies in Argentinean patients with variegate porphyria
title_full Genetic and biochemical studies in Argentinean patients with variegate porphyria
title_fullStr Genetic and biochemical studies in Argentinean patients with variegate porphyria
title_full_unstemmed Genetic and biochemical studies in Argentinean patients with variegate porphyria
title_sort genetic and biochemical studies in argentinean patients with variegate porphyria
publishDate 2008
url https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_14712350_v9_n_p_Rossetti
http://hdl.handle.net/20.500.12110/paper_14712350_v9_n_p_Rossetti
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AT giudicejimena geneticandbiochemicalstudiesinargentineanpatientswithvariegateporphyria
AT pareravictoriaestela geneticandbiochemicalstudiesinargentineanpatientswithvariegateporphyria
AT batllealciramariadelcarmen geneticandbiochemicalstudiesinargentineanpatientswithvariegateporphyria
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spelling paper:paper_14712350_v9_n_p_Rossetti2023-06-08T16:17:19Z Genetic and biochemical studies in Argentinean patients with variegate porphyria Rossetti, María Victoria Granata, Bárbara Xoana Giudice, Jimena Parera, Victoria Estela Batlle, Alcira María del Carmen adenine alanine amino acid complementary DNA cytosine glutamic acid glycine guanine nucleic acid protoporphyrinogen oxidase RNA threonine thymine tryptophan valine flavoprotein heme mitochondrial protein PPOX protein, human protoporphyrinogen oxidase adolescent adult amino acid substitution Argentina article binding site chemical analysis child codon controlled study DNA flanking region DNA sequence exon family study female frameshift mutation gene amplification gene deletion gene insertion genetic analysis genetic code heterozygosity human intron major clinical study male missense mutation molecular biology mutational analysis nucleic acid base substitution nucleotide sequence porphyria variegata promoter region reverse transcription polymerase chain reaction RNA sequence RNA transcription signal transduction biosynthesis genetics heterozygote detection metabolism middle aged polymerase chain reaction porphyria variegata Adolescent Adult Exons Female Flavoproteins Frameshift Mutation Heme Heterozygote Detection Humans Male Middle Aged Mitochondrial Proteins Mutation, Missense Polymerase Chain Reaction Porphyria, Variegate Protoporphyrinogen Oxidase Sequence Analysis, DNA Background: A partial deficiency in Protoporphyrinogen oxidase (PPOX) produces the mixed disorder Variegate Porphyria (VP), the second acute porphyria more frequent in Argentina. Identification of patients with an overt VP is absolutely important because treatment depends on an accurate diagnosis but more critical is the identification of asymptomatic relatives to avoid acute attacks which may progress to death. Methods: We have studied at molecular level 18 new Argentinean patients biochemically diagnosed as VP. PPOX gene was amplified in one or in twelve PCR reactions. All coding exons, flanking intronic and promoter regions were manual or automatically sequenced. For RT-PCR studies RNA was retrotranscripted, amplified and sequenced. PPOX activity in those families carrying a new and uncharacterized mutation was performed. Results: All affected individuals harboured mutations in heterozygous state. Nine novel mutations and 3 already reported mutations were identified. Six of the novel mutations were single nucleotide substitutions, 2 were small deletions and one a small insertion. Three single nucleotide substitutions and the insertion were at exon-intron boundaries. Two of the single nucleotide substitutions, c.471G>A and c.807G>A and the insertion (c.388+3insT) were close to the splice donor sites in exons 5, 7 and intron 4 respectively. The other single nucleotide substitution was a transversion in the last base of intron 7, g.3912G>C (c.808-1G>C) so altering the consensus acceptor splice site. However, only in the first case the abnormal band showing the skipping of exon 5 was detected. The other single nucleotide substitutions were transversions: c.101A>T, c.995G>C and c.670 T>G that result in p.E34V, p.G332A and W224G aminoacid substitutions in exons 3, 10 and 7 respectively. Activity measurements indicate that these mutations reduced about 50% PPOX activity and also that they co-segregate with this reduced activity value. Two frameshift mutations, c.133delT and c.925delA, were detected in exons 3 and 9 respectively. The first leads to an early termination signal 22 codons downstream (p.S45fsX67) and the second leads to a stop codon 5 codons downstream (p.I309fsX314). One reported mutation was a missense mutation (p.G232R) and 2 were frameshift mutations: c.1082insC and 1043insT. The last mutation was detected in six new apparently unrelated Argentinean families. Conclusion: Molecular analysis in available family members revealed 14 individuals who were silent carriers of VP. Molecular techniques represent the most accurate approach to identify unaffected carriers and to provide accurate genetic counselling for asymptomatic individuals. The initial screening includes the insertion search. © 2008 Rossetti et al; licensee BioMed Central Ltd. Fil:Rossetti, M.V. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Granata, B.X. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Giudice, J. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Parera, V.E. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Batlle, A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 2008 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_14712350_v9_n_p_Rossetti http://hdl.handle.net/20.500.12110/paper_14712350_v9_n_p_Rossetti