Genetic Analysis of Afibrinogenemia and Hypofibrinogenemia: Novel Mutations in the FGB Gene in the Turkish Population

2020 ◽  
Vol 143 (6) ◽  
pp. 529-532
Author(s):  
Didem Torun  Özkan ◽  
Nazan Sarper ◽  
Nejat Akar
Keyword(s):  
Amino Acid ◽  
Autosomal Recessive ◽  
Adenine Nucleotide ◽  
Gene Mutations ◽  
Autosomal Recessive Disorder ◽  
Turkish Population ◽  
Chain Gene ◽  
Congenital Afibrinogenemia ◽  
Low Levels ◽  
First Time

<b><i>Introduction:</i></b> Congenital afibrinogenemia is a rare autosomal recessive disorder characterized by bleeding that varies from mild to severe and by complete absence or extremely low levels of plasma and platelet fibrinogen. Hypofibrinogenemia is characterized by fibrinogen levels &#x3c;1.5 g/L. <b><i>Objective:</i></b> In this study, we analyzed fibrinogen beta chain gene mutations in Turkish afibrinogenemia and hypofibrinogenemia patients. <b><i>Methods:</i></b> We evaluated 20 afibrinogenemia and hypofibrinogenemia patients and 80 healthy controls. We have sequenced all exons of the <i>FGB</i> gene using the DNA isolated from the peripheral blood samples of patients and controls. <b><i>Results and Conclusion:</i></b> We found a nonsense mutation in exon 4 at nucleotide 630 that encoded serine amino acid, and in the same exon a missense mutation of T to C at nucleotide 647, resulting in a transition from leucine to proline (p.L198P) in a child with hypofibrinogenemia. These mutations have been shown for the first time in the same patient of Turkish descent. Furthermore, there was a novel heterozygous guanine-to-adenine nucleotide change in exon 3. This caused the change of arginine amino acid to threonine amino acid at position 136 (p.A136T) in a protein, which has not been described in the literature before.

Missense mutations in the human β fibrinogen gene cause congenital afibrinogenemia by impairing fibrinogen secretion

Blood ◽  
2000 ◽  
Vol 95 (4) ◽  
pp. 1336-1341 ◽  
Author(s):  
Stefano Duga ◽  
Rosanna Asselta ◽  
Elena Santagostino ◽  
Sirous Zeinali ◽  
Tatjana Simonic ◽  
...  
Keyword(s):  
Autosomal Recessive ◽  
Autosomal Recessive Disorder ◽  
Chain Gene ◽  
Missense Mutations ◽  
Wild Type ◽  
Large Deletions ◽  
Congenital Afibrinogenemia ◽  
Low Levels ◽  
A Chain ◽  
Mutation Mechanisms

Congenital afibrinogenemia is a rare autosomal recessive disorder characterized by bleeding that varies from mild to severe and by complete absence or extremely low levels of plasma and platelet fibrinogen. Although several mutations in the fibrinogen genes associated with dysfibrinogenemia and hypofibrinogenemia have been described, the genetic defects of congenital afibrinogenemia are largely unknown, except for a recently reported 11-kb deletion of the fibrinogen A-chain gene. Nevertheless, mutation mechanisms other than the deletion of a fibrinogen gene are likely to exist because patients with afibrinogenemia showing no gross alteration within the fibrinogen cluster have been reported. We tested this hypothesis by studying the affected members of two families, one Italian and one Iranian, who had no evidence of large deletions in the fibrinogen genes. Sequencing of the fibrinogen genes in the 2 probands detected 2 different homozygous missense mutations in exons 7 and 8 of the Bβ-chain gene, leading to amino acid substitutions Leu353Arg and Gly400Asp, respectively. Transient transfection experiments with plasmids expressing wild-type and mutant fibrinogens demonstrated that the presence of either mutation was sufficient to abolish fibrinogen secretion. These findings demonstrated that missense mutations in the Bβ fibrinogen gene could cause congenital afibrinogenemia by impairing fibrinogen secretion.

A G-to-A mutation in IVS-3 of the human gamma fibrinogen gene causing afibrinogenemia due to abnormal RNA splicing

Blood ◽  
2000 ◽  
Vol 96 (7) ◽  
pp. 2501-2505 ◽  
Author(s):  
Maurizio Margaglione ◽  
Rosa Santacroce ◽  
Donatella Colaizzo ◽  
Davide Seripa ◽  
Gennaro Vecchione ◽  
...  
Keyword(s):  
Amino Acid ◽  
Rna Splicing ◽  
Messenger Rna ◽  
Stop Codon ◽  
Premature Stop Codon ◽  
Autosomal Recessive Disorder ◽  
Chain Gene ◽  
Hemorrhagic Diathesis ◽  
Reading Frame ◽  
Congenital Afibrinogenemia

Abstract Congenital afibrinogenemia is a rare autosomal recessive disorder characterized by a hemorrhagic diathesis of variable severity. Although more than 100 families with this disorder have been described, genetic defects have been characterized in few cases. An investigation of a young propositus, offspring of a consanguineous marriage, with undetectable levels of functional and quantitative fibrinogen, was conducted. Sequence analysis of the fibrinogen genes showed a homozygous G-to-A mutation at the fifth nucleotide (nt 2395) of the third intervening sequence (IVS) of the γ-chain gene. Her first-degree relatives, who had approximately half the normal fibrinogen values and showed concordance between functional and immunologic levels, were heterozygtes. The G-to-A change predicts the disappearance of a donor splice site. After transfection with a construct, containing either the wild-type or the mutated sequence, cells with the mutant construct showed an aberrant messenger RNA (mRNA), consistent with skipping of exon 3, but not the expected mRNA. Sequencing of the abnormal mRNA showed the complete absence of exon 3. Skipping of exon 3 predicts the deletion of amino acid sequence from residue 16 to residue 75 and shifting of reading frame at amino acid 76 with a premature stop codon within exon 4 at position 77. Thus, the truncated γ-chain gene product would not interact with other chains to form the mature fibrinogen molecule. The current findings show that mutations within highly conserved IVS regions of fibrinogen genes could affect the efficiency of normal splicing, giving rise to congenital afibrinogenemia.

A G-to-A mutation in IVS-3 of the human gamma fibrinogen gene causing afibrinogenemia due to abnormal RNA splicing

Blood ◽  
2000 ◽  
Vol 96 (7) ◽  
pp. 2501-2505
Author(s):  
Maurizio Margaglione ◽  
Rosa Santacroce ◽  
Donatella Colaizzo ◽  
Davide Seripa ◽  
Gennaro Vecchione ◽  
...  
Keyword(s):  
Amino Acid ◽  
Rna Splicing ◽  
Messenger Rna ◽  
Stop Codon ◽  
Premature Stop Codon ◽  
Autosomal Recessive Disorder ◽  
Chain Gene ◽  
Hemorrhagic Diathesis ◽  
Reading Frame ◽  
Congenital Afibrinogenemia

Congenital afibrinogenemia is a rare autosomal recessive disorder characterized by a hemorrhagic diathesis of variable severity. Although more than 100 families with this disorder have been described, genetic defects have been characterized in few cases. An investigation of a young propositus, offspring of a consanguineous marriage, with undetectable levels of functional and quantitative fibrinogen, was conducted. Sequence analysis of the fibrinogen genes showed a homozygous G-to-A mutation at the fifth nucleotide (nt 2395) of the third intervening sequence (IVS) of the γ-chain gene. Her first-degree relatives, who had approximately half the normal fibrinogen values and showed concordance between functional and immunologic levels, were heterozygtes. The G-to-A change predicts the disappearance of a donor splice site. After transfection with a construct, containing either the wild-type or the mutated sequence, cells with the mutant construct showed an aberrant messenger RNA (mRNA), consistent with skipping of exon 3, but not the expected mRNA. Sequencing of the abnormal mRNA showed the complete absence of exon 3. Skipping of exon 3 predicts the deletion of amino acid sequence from residue 16 to residue 75 and shifting of reading frame at amino acid 76 with a premature stop codon within exon 4 at position 77. Thus, the truncated γ-chain gene product would not interact with other chains to form the mature fibrinogen molecule. The current findings show that mutations within highly conserved IVS regions of fibrinogen genes could affect the efficiency of normal splicing, giving rise to congenital afibrinogenemia.

Congenital afibrinogenemia: identification and expression of a missense mutation in FGB impairing fibrinogen secretion

Blood ◽  
2003 ◽  
Vol 102 (13) ◽  
pp. 4413-4415 ◽  
Author(s):  
Dung Vu ◽  
Paula H. B. Bolton-Maggs ◽  
Jeremy R. Parr ◽  
Michael A. Morris ◽  
Philippe de Moerloose ◽  
...  
Keyword(s):  
Missense Mutation ◽  
Gene Mutations ◽  
Great Majority ◽  
Autosomal Recessive Disorder ◽  
Homozygous Deletion ◽  
Chain Gene ◽  
Missense Mutations ◽  
Exon 2 ◽  
Congenital Afibrinogenemia ◽  
The Media

Abstract Congenital afibrinogenemia is a rare autosomal recessive disorder characterized by complete absence of detectable fibrinogen. We previously identified the first causative mutations for this disease: a homozygous deletion of approximately 11 kb of the fibrinogen α-chain gene (FGA). Subsequent studies revealed that the great majority of afibrinogenemia mutations are localized in FGA, but mutations were also found in FGG and FGB. Apart from 3 missense mutations identified in the C-terminal portion of FGB, all fibrinogen gene mutations responsible for afibrinogenemia are null. In this study, a young boy with afibrinogenemia was found to be a compound heterozygote for 2 mutations in FGB: an N-terminal nonsense mutation W47X (exon 2) and a missense mutation (G444S, exon 8). Coexpression of the FGB G444S mutant cDNA in combination with wild-type FGA and FGG cDNAs demonstrated that fibrinogen molecules containing the mutant β chain are able to assemble but are not secreted into the media, confirming the pathogenic nature of the identified mutation. (Blood. 2003;102:4413-4415)

Prenatal diagnosis for congenital afibrinogenemia caused by a novel nonsense mutation in the FGB gene in a Palestinian family

Blood ◽  
2003 ◽  
Vol 101 (9) ◽  
pp. 3492-3494 ◽  
Author(s):  
Marguerite Neerman-Arbez ◽  
Dung Vu ◽  
Bassam Abu-Libdeh ◽  
Isabelle Bouchardy ◽  
Michael A. Morris
Keyword(s):  
Prenatal Diagnosis ◽  
Nonsense Mutation ◽  
Autosomal Recessive ◽  
Direct Sequencing ◽  
Autosomal Recessive Disorder ◽  
Causative Mutation ◽  
Chain Gene ◽  
Congenital Afibrinogenemia ◽  
The Media ◽  
Homozygous Deletions

Congenital afibrinogenemia is a rare autosomal recessive disorder characterized by the complete absence of detectable fibrinogen. We previously identified the first causative mutations for this disease, homozygous deletions of approximately 11 kb of the fibrinogen alpha chain gene (FGA). Subsequent analyses revealed that most afibrinogenemia alleles are truncating mutations of FGA, although mutations in all 3 fibrinogen genes, FGG, FGA andFGB have been identified. In this study, we performed the first prenatal diagnosis for afibrinogenemia. The causative mutation in a Palestinian family was a novel nonsense mutation in theFGB gene, Trp467Stop (W467X). Expression of the Trp467Stop mutant FGB cDNA in combination with wild-typeFGA and FGG cDNAs showed that fibrinogen molecules containing the mutant beta chain are not secreted into the media. The fetus was found to be heterozygous for the Trp467Stop mutation by direct sequencing and by linkage analysis, a result that was confirmed in the newborn by intermediate fibrinogen levels.

Molecular genetic diagnostics of Bardet-Biedl syndrome with an MPS-panel

2021 ◽  
pp. 26-35
Author(s):  
М.Д. Орлова ◽  
П. Гундорова ◽  
А.В. Поляков
Keyword(s):  
Autosomal Recessive ◽  
Molecular Genetic ◽  
Autosomal Recessive Disorder ◽  
Genetic Diagnostics ◽  
Bardet Biedl Syndrome ◽  
Pathogenic Variants ◽  
Development Delay ◽  
Molecular Genetic Diagnostics ◽  
First Time

Синдром Барде-Бидля - аутосомно-рецессивное заболевание, характеризующееся ожирением, пигментной дегенерацией сетчатки, полидактилией, задержкой психоречевого развития и структурными повреждениями почек. В работе представлены результаты применения МПС-панели, включающей кодирующие последовательности и прилегающие интронные области 21 гена, ассоциированного с синдромом Барде-Бидля. Впервые была проведена молекулярно-генетическая диагностика в группе из сорока российских пациентов с синдромом Барде-Бидля из неродственных семей. В результате исследования удалось подтвердить диагноз молекулярно-генетическим методом у 40% пациентов (n=16). В генах BBS1, BBS7 и BBS10 встретились повторяющиеся варианты. Частота встречаемости патогенных и вероятно патогенных вариантов в генах BBS1 и BBS10 у российских пациентов соответствует зарубежным данным. Варианты в гене BBS7 встретились у пяти человек, у четырех из них был обнаружен патогенный вариант c.1967_1968delTAinsC, не встречающийся в других популяциях. Результаты, представленные в статье, показывают значительный вклад в заболеваемость синдромом Барде-Бидля в российской популяции патогенных вариантов в гене BBS7. Bardet-Biedl syndrome is an autosomal recessive disorder characterized by obesity, retinitis pigmentosa, polydactyly, development delay, and structural kidney defects. This study shows the results of using an MPS panel that includes coding sequences and intronic areas of 21 genes associated with Bardet-Biedl syndrome. For the first time molecular genetic testing has been provided for the group of 40 Russian patiens with Bardet-Biedl syndrome from unrelated families. As a result of the testing, diagnoses were confirmed for 40% of the patients (n=16). The genes BBS1, BBS7, BBS10 had recurrent variants. The frequency of pathogenic and likely pathogenic variants in the genes BBS1 and BBS10 among Russian patients matches the research data in other countries. Variants in the BBS7 gene were found for five people, four of them had a pathogenic variant c.1967_1968delTAinsC, which is not present among other populations. Results provided in this article show the significant role of pathogenic variants in the BBS7 gene in patients with Bardet-Biedl syndrome in Russian population.

Abetalipoproteinemia Presenting as Severe Vitamin K Deficiency

PEDIATRICS ◽  
1980 ◽  
Vol 65 (1) ◽  
pp. 161-163
Author(s):  
Fernan M. Caballero ◽  
George R. Buchanan
Keyword(s):  
Vitamin K ◽  
Autosomal Recessive ◽  
Neonatal Period ◽  
Chronic Diarrhea ◽  
Autosomal Recessive Disorder ◽  
Vitamin K Deficiency ◽  
History Of ◽  
K Deficiency ◽  
First Time ◽  
To Receive

Vitamin K deficiency has occasionally been observed in infants after the immediate neonatal period when one or more of the following features is present: diet consisting entirely of breast milk, failure to receive prophylactic vitamin K shortly after birth, therapy with broad-spectrum antibiotics, or chronic diarrhea accompanying malabsorption due to cystic fibrosis or to various acquired causes.1-7 In this report we describe for the first time an infant with the uncommon autosomal recessive disorder abetalipoproteinemia whose major presenting manifestation in early infancy was hemorrhage due to vitamin K deficiency. CASE REPORT A 6-week-old baby was brought in for evaluation because of a two- to three-week history of easy bruising.

scholarly journals Juvenile Hemochromatosis: A Case Report and Review of the Literature

2020 ◽  
Vol 13 (8) ◽  
pp. 195
Author(s):  
Akiyoshi Takami ◽  
Yasuaki Tatsumi ◽  
Katsuhisa Sakai ◽  
Yasumichi Toki ◽  
Katsuya Ikuta ◽  
...  
Keyword(s):  
Autosomal Recessive ◽  
Age Of Onset ◽  
Relevant Literature ◽  
Autosomal Recessive Disorder ◽  
Age Difference ◽  
Outpatient Basis ◽  
Review Of The Literature ◽  
Hepcidin Expression ◽  
Juvenile Hemochromatosis ◽  
First Time

Juvenile hemochromatosis (JH), type 2A hemochromatosis, is a rare autosomal recessive disorder of systemic iron overload due to homozygous mutations of HJV (HFE2), which encodes hemojuvelin, an essential regulator of the hepcidin expression, causing liver fibrosis, diabetes, and heart failure before 30 years of age, often with fatal outcomes. We report two Japanese sisters of 37 and 52 years of age, with JH, who showed the same homozygous HJV I281T mutation and hepcidin deficiency and who both responded well to phlebotomy on an outpatient basis. When all reported cases of JH with homozygous HJV mutations in the relevant literature were reviewed, we found—for the first time—that JH developed in females and males at a ratio of 3:2, with no age difference in the two groups. Furthermore, we found that the age of onset of JH may depend on the types of HJV mutations. In comparison to patients with the most common G320V/G320V mutation, JH developed earlier in patients with L101P/L101P or R385X/R385X mutations and later in patients with I281T/I281T mutations.

scholarly journals Prevalence of CYP17A1 gene mutations in 17α-hydroxylase deficiency in the Chinese Han population

2019 ◽  
Vol 25 (1) ◽  
Author(s):  
Menglin Wang ◽  
Hao Wang ◽  
Haiying Zhao ◽  
Ling Li ◽  
Min Liu ◽  
...  
Keyword(s):  
Autosomal Recessive ◽  
Gene Mutations ◽  
Autosomal Recessive Disorder ◽  
Chinese Han ◽  
Hydroxylase Deficiency ◽  
Case Presentation ◽  
Chinese Populations ◽  
Pathogenic Variants ◽  
Cytochrome P450 Family ◽  
Chinese Girls

Abstract Background 17α-hydroxylase deficiency is a rare autosomal recessive disorder caused by mutations in the cytochrome P450 family 17 subfamily A member 1 gene. The major clinical presentation includes hypertension, hypokalemia, male pseudohermaphroditism and female gonadal dysplasia. Hundreds of pathogenic variants have been reported in this disorder, and some common mutations were found to be race-specific. Case presentation In this study, we reported 5 Chinese girls with 17α-hydroxylase deficiency from Henan Province. The patients all came to the hospital for hypertension, and they also presented with sexual infantilism. The average age of the patients was 14 years old, ranging from 12 to 17 years old. They all had reduced blood cortisol, estradiol (E2), and testosterone (TESTO) and increased adrenocorticotropic hormone (ACTH), follicle-stimulating hormone (FSH), and luteinizing hormone (LH). They all had the appearance of females; however, three of the chromosome karyotypes were 46XX, and two were 46XY. Conclusions All of the patients carried a mutation on the 329 amino acid of CYP17A1 exon 6. By summarizing the currently known pathogenic mutations of 17α-hydroxylase deficiency, we demonstrated the prevalence of these gene mutations in Chinese Han and non-Chinese populations.

scholarly journals N-Acetylglutamate and its changing role through evolution

2003 ◽  
Vol 372 (2) ◽  
pp. 279-290 ◽  
Author(s):  
Ljubica CALDOVIC ◽  
Mendel TUCHMAN
Keyword(s):  
Amino Acid ◽  
Autosomal Recessive ◽  
Urea Cycle ◽  
Evolutionary Relationship ◽  
Autosomal Recessive Disorder ◽  
The Other ◽  
Arginine Biosynthesis ◽  
Carbamyl Phosphate ◽  
Carbamyl Phosphate Synthetase ◽  
Changing Role

N-Acetylglutamate (NAG) fulfils distinct biological roles in lower and higher organisms. In prokaryotes, lower eukaryotes and plants it is the first intermediate in the biosynthesis of arginine, whereas in ureotelic (excreting nitrogen mostly in the form of urea) vertebrates, it is an essential allosteric cofactor for carbamyl phosphate synthetase I (CPSI), the first enzyme of the urea cycle. The pathway that leads from glutamate to arginine in lower organisms employs eight steps, starting with the acetylation of glutamate to form NAG. In these species, NAG can be produced by two enzymic reactions: one catalysed by NAG synthase (NAGS) and the other by ornithine acetyltransferase (OAT). In ureotelic species, NAG is produced exclusively by NAGS. In lower organisms, NAGS is feedback-inhibited by l-arginine, whereas mammalian NAGS activity is significantly enhanced by this amino acid. The NAGS genes of bacteria, fungi and mammals are more diverse than other arginine-biosynthesis and urea-cycle genes. The evolutionary relationship between the distinctly different roles of NAG and its metabolism in lower and higher organisms remains to be determined. In humans, inherited NAGS deficiency is an autosomal recessive disorder causing hyperammonaemia and a phenotype similar to CPSI deficiency. Several mutations have been recently identified in the NAGS genes of families affected with this disorder.

Sign in / Sign up

Export Citation Format

Share Document