Mutations in the AML1 Gene Define an Unfavorable Subgroup in Acute Myeloid Leukemia with FAB M0.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 4340-4340
Author(s):  
Frank Dicker ◽  
Mirjam Klaus ◽  
Torsten Haferlach ◽  
Wolfgang Kern ◽  
Wolfgang Hiddemann ◽  
...  
Keyword(s):  
High Performance ◽  
De Novo ◽  
Mutation Screening ◽  
Point Mutations ◽  
Gene Mutations ◽  
Normal Karyotype ◽  
Runt Domain ◽  
Screening Efficiency ◽  
Genetic Aberration ◽  
Aml1 Gene

Abstract The AML1/RUNX1 gene is the most frequent target for chromosomal translocations in leukemia. Recently point mutations in the AML1 gene have been demonstrated as another mode of genetic aberration. AML1 mutations have been reported in de novo MDS and AML, as well as in therapy related MDS and AML. The AML M0 subtype has been found to be most frequently affected by sporadic AML1 gene mutations. We analysed AML1 gene mutations in a cohort of 49 M0 patients. Mutation screening was performed either with SSCP (n=21) and/or denaturating High Performance Liquid Chromatography (dHPLC) (n=33), 5 cases were analyzed by both methods. SSCP screening of exons 3–5 of the AML1 gene was carried out at the genomic level. These exons cover the socalled Runt domain, which is most frequently mutated. Fragments with aberrant mobility were sequenced. With this method 5 cases were found to be mutated. Subsequently, to improve the screening efficiency an assay using dHPLC was established. Hereby, we screened the cDNA of patient samples for mutations in amino acid codons 1–277 of the AML1b transcript, where the Runt domain is located between codons 49 and 178. All 5 cases detected by SSCP were confirmed by dHPLC. Nine mutations were detected in the cohort of 28 cases (32%) which had not been analyzed by SSCP. In total, 14 of the 49 samples (29%) tested were identified to be mutated, which is a slightly higher frequency than previously reported. In the cohort of 35 AML1 non-mutated cases 20 (57%) had a normal karyotype and 15 (43%) an aberrant karyotypes, whereas only 6 of the 14 AML1 mutated cases (43%) had a normal karyotype (p=0.001). Three of the AML1 mutated cases (21%) also had FLT3 mutations. One had an FLT3-LM, one an FLT3-TKD mutation, and one case both LM and TKD mutations. Clinical follow up data were available for 33 patients (22 AML1 non- mutated, 11 AML1 mutated). The median OS and EFS of the AML1 non-mutated versus the mutated group was 276 days versus 63 days (p = 0.0679) and 276 vs. 63 days (p=0.0630) respectively. Thus the AML1 mutated cases tend to have a worse clinical outcome. When other AML subtypes were screened for AML1 mutations, i.e. M1 (n=26), M2 (n=21) and M4 (n=3), only 1 additional AML1 mutation was detected, confirming the highest prevalence of AML1 mutations in M0. In conclusion, 1) we established a new assay to screen for AML1 mutations. 2) We confirmed the high incidence of AML1 gene mutations in AML M0, both in cases with normal and aberrant karyotype. 3) For the first time we demonstrated that AML1 mutations define an unfavorable subentity in AML M0.

JAK2 Mutation Screening and Chromosome Analysis Are Necessary for a Comprehensive Diagnostic Work up in CMPD: A Study on 469 Cases.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 4963-4963
Author(s):  
Susanne Schnittger ◽  
Torsten Haferlach ◽  
Petro E. Petrides ◽  
Wolfgang Kern ◽  
Claudia Schoch
Keyword(s):  
De Novo ◽  
Blast Crisis ◽  
Mutation Screening ◽  
Melting Curve ◽  
Therapy Response ◽  
Normal Karyotype ◽  
Chromosome Analysis ◽  
Molecular Monitoring ◽  
Jak2 Mutation ◽  
De Novo Aml

Abstract The diagnosis of BCR-ABL negative chronic myeloproliferative disorders (CMPD) is still a challenge for the morphologist and clinician, mainly because of overlapping phenotypes of essential thrombocythemia (ET), polycythemia vera (PV), idiopathic myelofibrosis (IMF) and non-malignant reactive phenotypes. Recently, a new mutation in JAK2 leading to V617F exchange in exon 12 was described in these entities. Therefore, we developed a rapid and easy LightCycler based melting curve assay and screened 469 patients with various malignancies for the respective JAK2 mutation using cDNA prepared from mononucleated cells. All cases tested positive were confirmed by sequencing and without any exception all mutations were G to T exchanges at nucleotide 1849. In total, 61 cases with PV were analysed. 56 (91.8%) were mutated (see table). A karyotype was available in 36 cases. Of the JAK2- cases 4 had normal karyotypes and one 20q-. Of the JAK2+ cases 21 had normal karyotype; four (7.1%) had +9, one +8, one +22, one 20q-, and three showed a complex aberrant karyotype. Of the 47 analyzed ET 26 (55%) were mutated. Cytogenetics was available in 20 cases (9 JAK2-, 11 JAK2+). All JAK2- cases all had normal karyotypes. Of the JAK2+ 10 had a normal karyotype and one a t(9;13)(p24;q22) involving the JAK2 locus. Of the 25 IMF cases 14 (56%) were mutated. Karyotype was available in 17 cases (7 JAK2-, 10 JAK2+). All 7 JAK2- had normal karyotype. Of the 10 JAK2+ 6 had normal karyotype and four were aberrant (+9:n=2; 20q-: n=2). In addition, 2/7 cases (28.6%) with CMML were JAK2+. Furthermore, we analysed 89 BCR-ABL negative MPS that were not further specified. V617F was detectable in 43 patients (48.3%). At next 128 AML were analyzed (84 novo AML, 11 t-AML after a previous malignancy, 15 secondary to MDS, and 16 secondary to MPS (PV:n=7, ET:n=5, OMF:n=2). No V617F was detected in all cases with t-AML and s-AML after MDS. In contrast, in de novo AML 6/84 (7.1%) were JAK2+, of which 4 were proven homozygous. Surprisingly, 4 of these six cases had a +9. In AML secondary to a previous CMPD 11/16 (68.8 %) were JAK2+. Of these 2 had +9, one a normal karyotype and 12 a complex aberrant karyotype. These data suggest that acquisition of +9 may lead to progress or blast crisis in JAK2 mutated MPS and supports the gain of function mechanism of the mutation. In conclusion, more than half of all BCR-ABL-negative MPS harbour a V617F mutation. This helps in the differential diagnosis of MPS versus reactive disorders. V617F is more frequently associated with aberrant karyotype than wildtype JAK2. In addition, there is an increasing level of aberrant cytogenetics and mutation rate with respect to incidence and status from ET<IMF<PV indicating that these diseases might be overlapping or even a continuum. It demonstrates that the present classification is artificial and a new classification of “JAK2” positive diseases may be more adequate. In addition, the same mutation was observed in most cases of AML secondary to CMPD. It was also found in few cases with de novo AML and correlated with +9. JAK2V617F is a new and promising target for therapy as well as for molecular monitoring of therapy response in CMPD. Distribution of JAK2 mutation in various malignancies ET IMF PV MPS* CMML de novo AML AML after MPS *not further specified total 47 25 61 89 7 84 16 mutated (n=) 26 14 56 43 2 6 11 mutated (% of all) 55.0 % 56.0 % 91.8 % 48.3 % 28.6 % 7.1 % 68.8 % homozygous (n=) 3 9 33 19 1 4 7 homozygous (% of all) 6.4 % 36.0 % 54.1 % 21.3 % 14.3 % 4.8 % 43.8 %

High incidence of biallelic point mutations in the Runt domain of the AML1/PEBP2αB gene in Mo acute myeloid leukemia and in myeloid malignancies with acquired trisomy 21

Blood ◽  
2000 ◽  
Vol 96 (8) ◽  
pp. 2862-2869 ◽  
Author(s):  
Claude Preudhomme ◽  
Delphine Warot-Loze ◽  
Christophe Roumier ◽  
Nalthalie Grardel-Duflos ◽  
Richard Garand ◽  
...  
Keyword(s):  
Trisomy 21 ◽  
Myeloid Leukemia ◽  
Stop Codon ◽  
Point Mutations ◽  
Chromosome 21 ◽  
Runt Domain ◽  
Myeloid Malignancies ◽  
Aml1 Gene ◽  
Atypical Cml ◽  
Acute Myeloid

Abstract The AML1 gene, situated in 21q22, is often rearranged in acute leukemias through t(8;21) translocation, t(12;21) translocation, or less often t(3;21) translocation. Recently, point mutations in the Runt domain of the AML1 gene have also been reported in leukemia patients. Observations for mutations of the Runt domain of the AML1 gene in bone marrow cells were made in 300 patients, including 131 with acute myeloid leukemia (AML), 94 with myelodysplastic syndrome (MDS), 28 with blast crisis chronic myeloid leukemia (CML), 3 with atypical CML, 41 with acute lymphoblastic leukemia (ALL), and 3 with essential thrombocythemia (ET). Forty-one of the patients had chromosome 21 abnormalities, including t(8;21) in 6 of the patients with AML, t(12;21) in 8 patients with ALL, acquired trisomy 21 in 17 patients, tetrasomy 21 in 7 patients, and constitutional trisomy 21 (Down syndrome) in 3 patients. A point mutation was found in 14 cases (4.7%), including 9 (22%) of the 41 patients with AML of the Mo type (MoAML) (none of them had detectable chromosome 21 rearrangement) and 5 (38%) of the 13 myeloid malignancies with acquired trisomy 21 (1 M1AML, 2 M2AML, 1 ET, and 1 atypical CML). In at least 8 of 9 mutated cases of MoAML, both AML alleles were mutated: 3 patients had different stop codon mutations of the 2 AML1 alleles, and 5 patients had the same missense or stop codon mutation in both AML1 alleles, which resulted in at least 3 of the patients having duplication of the mutated allele and deletion of the normal residual allele, as shown by FISH analysis and by comparing microsatellite analyses of several chromosome 21 markers on diagnosis and remission samples. In the remaining mutated cases, with acquired trisomy 21, a missense mutation of AML1, which involved 2 of the 3 copies of the AML1 gene, was found. Four of the 7 mutated cases could be reanalyzed in complete remission, and no AML1 mutation was found, showing that mutations were acquired in the leukemic clone. In conclusion, these findings confirm the possibility of mutations of the Runt domain of the AML1 gene in leukemias, mainly in MoAML and in myeloid malignancies with acquired trisomy 21. AML1 mutations, in MoAML, involved both alleles and probably lead to nonfunctional AML1 protein. As AML1 protein regulates the expression of the myeloperoxidase gene, the relationship between AML1 mutations and Mo phenotype in AML will have to be further explored.

scholarly journals DHPLC Screening ofATMGene in Italian Patients Affected by Ataxia-Telangiectasia: Fourteen NovelATMMutations

2006 ◽  
Vol 22 (4) ◽  
pp. 257-264 ◽  
Author(s):  
Monia Magliozzi ◽  
Maria Piane ◽  
Isabella Torrente ◽  
Lorenzo Sinibaldi ◽  
Giovanni Rizzo ◽  
...  
Keyword(s):  
Ataxia Telangiectasia ◽  
Hot Spots ◽  
Genomic Dna ◽  
High Performance ◽  
Detection Rate ◽  
Mutation Screening ◽  
Gene Mutations ◽  
Positive Control ◽  
High Incidence ◽  
Atm Gene

The gene for ataxia-telangiectasia (A-T:MIM:#208900), ATM, spans about 150~kb of genomic DNA and is composed of 62 coding exons. ATM mutations are found along the entire coding sequence of the gene, without evidence of mutational hot spots. Using DNA as the starting material, we used denaturing high performance liquid chromatography (DHPLC) technique to search for ATM gene mutations. Initially, DHPLC was validated in a retrospective study of 16 positive control samples that included 19 known mutations; 100% of mutations were detected. Subsequently, DHPLC was used to screen for mutations a cohort of 22 patients with the classical form of A-T. A total of 27 different mutations were identified on 38 of the 44 alleles, corresponding to a 86% detection rate. Fourteen of the mutations were novel. In addition, 15 different variants and polymorphisms of unknown functional significance were found. The high incidence of new and individual A-T mutations in our cohort of patients demonstrates marked mutational heterogeneity of A-T in Italy and corroborate the efficiency of DHPLC as a method for the mutation screening of A-T patients.

STUDY OF THE AVERAGE AGE OF OCCURRENCE OF GENE MUTATIONS IN ACUTE MYELOMONOBLASTIC LEUKEMIA

2020 ◽  
Vol 17 (3) ◽  
pp. 206-209
Author(s):  
A.V. Vinogradov ◽  
Keyword(s):  
Chromosomal Abnormalities ◽  
Point Mutations ◽  
Gene Mutations ◽  
Normal Karyotype ◽  
Tp53 Gene ◽  
The Elderly ◽  
Chain Reaction ◽  
Sequencing Method ◽  
Polymerase Chain ◽  
Detection Of Mutations

Aim: to determine the average age of occurrence of gene mutations in acute myelomonoblastic leukemia (AMML). Materials and methods. Bone marrow and peripheral blood samples from 40 patients (average age 50 years, including 13 aged 15 to 45 years, 15 aged 45-60 years, 12 aged over 60 years) with newly detected AMML were examined. Detection of chromosomal abnormalities was performed using standard cytogenetic and real-time polymerase chain reaction methods. Point mutations were screened in 8 genes: FLT3 (n=35), NPM1 (n=25), TP53 (n=24), C-KIT (n=23), NRAS (n=19), WT1 (n=18), DNMT3A (n=13), and KRAS (n=4) by direct automatic sequencing method. Results. The majority of patients (56.3%) had a normal karyotype, 15.6% had aneuploid karyotype, and 28.1% had other structural and quantitative chromosome abnormalities. 35.0% of patients had point mutations in the studied genes at the time of diagnosis of OMML. The highest mutation rates were found for the DNMT3A (30.8%), NPM1 (20.0%), and FLT3 (20.0%) genes. The frequency of double mutants was 15.2%. The average age of detection of mutations in the c-KIT and NPM1 genes corresponded to young adults (33.5±2.9 and 44.2±11.4, respectively), for 3 genes — to middle age (DNMT3A — 49.3±18.4; WT1 — 51.0; FLT3 — 54.0±12.3), for the TP53 gene — to the elderly (n=1, 63 years). The average age of double mutants was 42.2±13.7 years due to NPM1 and c-KIT co-mutations.

Ferrochelatase Mutation Screening by Denaturing High Performance Liquid Chomatography in Idiopathic Acquired Sideroblastic Anemia (Refractory Anemia with Ringed Sideroblasts) and Erythrocytic Protoporphyria.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 3735-3735
Author(s):  
Kathleen A. Hecksel ◽  
Gordon W. Dewald ◽  
David P. Steensma
Keyword(s):  
High Performance ◽  
Mutation Screening ◽  
Point Mutations ◽  
Refractory Anemia ◽  
Coding Region ◽  
Sideroblastic Anemia ◽  
Ringed Sideroblasts ◽  
Proper Form ◽  
Molecular Etiology ◽  
Normal Urine

Abstract BACKGROUND: The molecular etiology of idiopathic acquired sideroblastic anemia (IASA), now considered a form of myelodysplastic syndrome, is currently unknown. Romslo et al (Blood 1982) reported a patient with IASA who had moderately elevated free erythrocytic protoporphyrin (FEP); this observation is now frequently made in IASA, helping distinguish IASA (high FEP) from inherited sideroblastosis (low FEP). In addition, rare patients with erythropoietic protoporphyria (EPP)—defined by cutaneous photosensitivity, dramatically elevated FEP levels, and germline point mutations in the ferrochelatase (FECH) gene at 18q21.3—have ringed sideroblasts in their marrow. We hypothesized that patients with IASA might have acquired somatic FECH mutations. METHODS AND RESULTS: We designed a denaturing high performance liquid chromatography (DHPLC) assay to explore this possibility and to avoid problems related to mutation screening in the setting of mixed clonality. To validate the DHPLC assay, the coding region of the FECH gene from 2 molecularly undiagnosed EPP patients without liver disease was analyzed. In one patient, both a heterozygous 69delG mutation (GenBank Accession NM_000140) and heterozygosity for the FECH expression-modulating IVS3-48C/T polymorphism were detected. In the other patient, no FECH coding mutations or polymorphisms were detected, either by DHPLC or conventional dye sequencing. FEP measurements were then obtained on 2 IASA patients and were elevated (65 and 115 mcg/dL; normal 1–10 mcg/dL) with normal urine and fecal porphyrins. Genomic DNA obtained from these 2 patients as well as archival DNA from 30 other patients with IASA was amplified and tested for FECH mutations. No coding region mutations were detected. Synonymous polymorphisms in exon 7 (rs536765) and 9 (rs536560) were found in 6/32 (19%; normal heterozygosity 0.398) and 14/32 (44%; normal heterozygosity 0.402) samples, respectively. The IVS3-48C/T polymorphism (rs2272783) was found in 3/32 (9%) (prevalence in the general population is 11%, Gouya Nat Genet 2002). In addition, 3 intronic polymorphisms not in the refSNP database were detected: IVS8+34 C/T (2/32), IVS8-61delG (5/32), and IVS9-59delA (2/32). CONCLUSION: IASA is not associated with coding mutations in FECH. Elevation of FEP in ASA must instead be due to the lack of mitochondrial iron in the proper form for incorporation into the porphyrin ring; attention should instead focus on factors responsible for maintaining the appropriate redox state and compartmentalization of iron. DHPLC can detect FECH mutations and polymorphisms, but because of the high frequency of the latter and the consequent need to sequence multiple exons, it is not a practical screening tool for studying undiagnosed EPP patients.

High incidence of biallelic point mutations in the Runt domain of the AML1/PEBP2αB gene in Mo acute myeloid leukemia and in myeloid malignancies with acquired trisomy 21

Blood ◽  
2000 ◽  
Vol 96 (8) ◽  
pp. 2862-2869 ◽  
Author(s):  
Claude Preudhomme ◽  
Delphine Warot-Loze ◽  
Christophe Roumier ◽  
Nalthalie Grardel-Duflos ◽  
Richard Garand ◽  
...  
Keyword(s):  
Trisomy 21 ◽  
Myeloid Leukemia ◽  
Stop Codon ◽  
Point Mutations ◽  
Chromosome 21 ◽  
Runt Domain ◽  
Myeloid Malignancies ◽  
Aml1 Gene ◽  
Atypical Cml ◽  
Acute Myeloid

The AML1 gene, situated in 21q22, is often rearranged in acute leukemias through t(8;21) translocation, t(12;21) translocation, or less often t(3;21) translocation. Recently, point mutations in the Runt domain of the AML1 gene have also been reported in leukemia patients. Observations for mutations of the Runt domain of the AML1 gene in bone marrow cells were made in 300 patients, including 131 with acute myeloid leukemia (AML), 94 with myelodysplastic syndrome (MDS), 28 with blast crisis chronic myeloid leukemia (CML), 3 with atypical CML, 41 with acute lymphoblastic leukemia (ALL), and 3 with essential thrombocythemia (ET). Forty-one of the patients had chromosome 21 abnormalities, including t(8;21) in 6 of the patients with AML, t(12;21) in 8 patients with ALL, acquired trisomy 21 in 17 patients, tetrasomy 21 in 7 patients, and constitutional trisomy 21 (Down syndrome) in 3 patients. A point mutation was found in 14 cases (4.7%), including 9 (22%) of the 41 patients with AML of the Mo type (MoAML) (none of them had detectable chromosome 21 rearrangement) and 5 (38%) of the 13 myeloid malignancies with acquired trisomy 21 (1 M1AML, 2 M2AML, 1 ET, and 1 atypical CML). In at least 8 of 9 mutated cases of MoAML, both AML alleles were mutated: 3 patients had different stop codon mutations of the 2 AML1 alleles, and 5 patients had the same missense or stop codon mutation in both AML1 alleles, which resulted in at least 3 of the patients having duplication of the mutated allele and deletion of the normal residual allele, as shown by FISH analysis and by comparing microsatellite analyses of several chromosome 21 markers on diagnosis and remission samples. In the remaining mutated cases, with acquired trisomy 21, a missense mutation of AML1, which involved 2 of the 3 copies of the AML1 gene, was found. Four of the 7 mutated cases could be reanalyzed in complete remission, and no AML1 mutation was found, showing that mutations were acquired in the leukemic clone. In conclusion, these findings confirm the possibility of mutations of the Runt domain of the AML1 gene in leukemias, mainly in MoAML and in myeloid malignancies with acquired trisomy 21. AML1 mutations, in MoAML, involved both alleles and probably lead to nonfunctional AML1 protein. As AML1 protein regulates the expression of the myeloperoxidase gene, the relationship between AML1 mutations and Mo phenotype in AML will have to be further explored.

scholarly journals Diazoxide-responsive hyperinsulinemic hypoglycemia caused by HNF4A gene mutations

2010 ◽  
Vol 162 (5) ◽  
pp. 987-992 ◽  
Author(s):  
S E Flanagan ◽  
R R Kapoor ◽  
G Mali ◽  
D Cody ◽  
N Murphy ◽  
...  
Keyword(s):  
Family History ◽  
De Novo ◽  
Clinical Phenotype ◽  
Mutation Screening ◽  
Genetic Diagnosis ◽  
Gene Mutations ◽  
Hyperinsulinemic Hypoglycemia ◽  
Neonatal Hypoglycemia ◽  
Family History Of Diabetes ◽  
History Of

ObjectiveThe phenotype associated with heterozygous HNF4A gene mutations has recently been extended to include diazoxide responsive neonatal hypoglycemia in addition to maturity-onset diabetes of the young (MODY). To date, mutation screening has been limited to patients with a family history consistent with MODY. In this study, we investigated the prevalence of HNF4A mutations in a large cohort of patients with diazoxide responsive hyperinsulinemic hypoglycemia (HH).Subjects and methodsWe sequenced the ABCC8, KCNJ11, GCK, GLUD1, and/or HNF4A genes in 220 patients with HH responsive to diazoxide. The order of genetic testing was dependent upon the clinical phenotype.ResultsA genetic diagnosis was possible for 59/220 (27%) patients. KATP channel mutations were most common (15%) followed by GLUD1 mutations causing hyperinsulinism with hyperammonemia (5.9%), and HNF4A mutations (5%). Seven of the 11 probands with a heterozygous HNF4A mutation did not have a parent affected with diabetes, and four de novo mutations were confirmed. These patients were diagnosed with HI within the first week of life (median age 1 day), and they had increased birth weight (median +2.4 SDS). The duration of diazoxide treatment ranged from 3 months to ongoing at 8 years.ConclusionsIn this large series, HNF4A mutations are the third most common cause of diazoxide responsive HH. We recommend that HNF4A sequencing is considered in all patients with diazoxide responsive HH diagnosed in the first week of life irrespective of a family history of diabetes, once KATP channel mutations have been excluded.

scholarly journals Genetic Variation Analysis and Treatment Strategy of 20 Patients with Dystrophin Gene Mutations

2020 ◽  
Author(s):  
Yedan Liu ◽  
Jun Chen ◽  
Mei Hou ◽  
Yanhui Zhang ◽  
Ya Guo ◽  
...  
Keyword(s):  
Muscular Dystrophy ◽  
Clinical Manifestation ◽  
De Novo ◽  
Point Mutations ◽  
Clinical Manifestations ◽  
Gene Mutations ◽  
Dystrophin Gene ◽  
Elevated Concentration ◽  
Genetic Sequencing ◽  
First Time

Abstract Background. Dystrophin (DMD) gene mutations canaffect muscular dystrophin isoform expression and result in progressive muscular dystrophy including Duchenne and Becker muscular dystrophies (DMD and BMD). To establish the correlation between phenotype and genotype and exemplify the current and future treatment for muscular dystrophy disorders, we investigated 20 patients suffering from a dystrophinopathy andsummarized clinical manifestation and gene mutations of them. Case presentation.The clinical manifestations, physical examination, laboratory work, and gene mutation results were collected in 20 patients with DMD or BMD diagnosed by clinical phenotype and genetic sequencing from July 2015 to December 2019. Multiplex ligation probe amplification (MLPA) and next-generation sequencing (NGS) were used to detect mutations in the DMD gene, and detected mutations were confirmed by Sanger sequencing. The clinical manifestation of patients was characterized by progressive symmetrical muscle degeneration, limb weakness, and pseudohypertrophy along with the elevated concentration of creatine kinase, alanine aminotransferase,and aspartate aminotransferase.We found 11 dystrophin gene deletions (55%) and 4 duplication mutations (20%) among the affected patients. However, we also found point mutations including 1 nonsense (20%), 3 frameshifts (60%), and 1 splice sites (20%) mutations in the rest 5 patients. Among the 15 cases of exon deletion or duplication mutations, 7 were inherited from the mother, 3 were de-novo, while the other 5 were not tested. Besides, all 5 point-mutation cases were inherited from the mother, among which 4 point mutations were identified for the first time and linked to the disease phenotype. Conclusions.We provided clinical portraits, genetic results, and the molecular effects of mutations in patients. Four novel point mutations were identified for the first time and associated with the development of DMD and BMD. Further, we expanded knowledge of the DMD variant spectrum and exemplified the emerging therapies in muscular dystrophy.

scholarly journals 126.A repository of ENU mutant mouse lines and their potential for male fertility research

2004 ◽  
Vol 16 (9) ◽  
pp. 126
Author(s):  
C. L. Kennedy ◽  
A. E. O’Connor ◽  
L. G. Sanchez-Partida ◽  
C. C. Goodnow ◽  
D. M. De Kretser ◽  
...  
Keyword(s):  
Male Fertility ◽  
High Performance ◽  
Large Scale ◽  
Mutation Screening ◽  
Point Mutations ◽  
Serum Levels ◽  
Reproductive Technologies ◽  
Specific Gene ◽  
Contraceptive Agents ◽  
Wide Range

One in 25 western men are infertile and the causal factor is frequently unknown, although it is expected that many are genetic in origin. My project aims to identify genes critical to mouse spermatogenesis using ENU mutagenesis. A further aim was to develop a repository of mutant mice and data on their fertility parameters for use by the reproductive biology community. This research will aid the diagnosis and development of specific treatments for human infertility and the development of contraceptive agents. The potent mutagen N-ethyl-N-nitrosourea (ENU) was utilized to generate libraries of C57BL/6 mice with random point mutations throughout their genomes. A 3 generational breeding program produced mice that were homozygous for a number of mutations. I subsequently performed a number of large scale screens on 3rd generation males, identifying lines carrying recessive mutations specifically affecting male fertility. Thus far we have observed a wide range of abnormal testis phenotypes including Sertoli Cell only, hypospermatogenesis, meiosis arrest, abnormal sperm morphology and abnormal hormone levels. From these analyses a repository including all data and tissues collected from 1200 3rd generation male mice from 122 different lines has been developed and will become publicly available. This includes testis and epididymal histology and serum levels of FSH, LH, activin A and inhibin. Further, I have stored gDNA long term and cryopreserved sperm to enable regeneration of lines in the future. In addition, I have developed a high throughput mutation screening protocol for the detection of mutations within genes of interest using denaturing high performance liquid chromatography (DHPLC). Collectively, our repository and gene screening techniques can be used in conjunction with artificial reproductive technologies to generate mouse models reflective of human conditions and altered specific gene function.

scholarly journals Genetic Variation Analysis and Treatment Strategy of 20 Patients with Dystrophin Gene Mutations

2020 ◽  
Author(s):  
Yedan Liu ◽  
Jun Chen ◽  
Mei Hou ◽  
Yanhui Zhang ◽  
Ya Guo ◽  
...  
Keyword(s):  
Muscular Dystrophy ◽  
Clinical Manifestation ◽  
De Novo ◽  
Point Mutations ◽  
Clinical Manifestations ◽  
Gene Mutations ◽  
Dystrophin Gene ◽  
Elevated Concentration ◽  
Genetic Sequencing ◽  
First Time

Abstract BackgroundDystrophin (DMD) gene mutations can affect muscular dystrophin isoform expression and result in progressive muscular dystrophy including Duchenne and Becker muscular dystrophies (DMD and BMD). To establish the correlation between phenotype and genotype and exemplify the current and future treatment for muscular dystrophy disorders, we investigated 20 patients suffering from a dystrophinopathy and summarized clinical manifestation and gene mutations of them. MethodsThe clinical manifestations, physical examination, laboratory work, and gene mutation results were collected in 20 patients with DMD or BMD diagnosed by clinical phenotype and genetic sequencing from July 2015 to December 2019. Multiplex ligation probe amplification (MLPA) and next-generation sequencing (NGS) were used to detect mutations in the DMD gene, and detected mutations were confirmed by Sanger sequencing. ResultsThe clinical manifestation of patients was characterized by progressive symmetrical muscle degeneration, limb weakness, and pseudohypertrophy along with the elevated concentration of creatine kinase, alanine aminotransferase, and aspartate aminotransferase. We found 11 dystrophin gene deletions (55%) and 4 duplication mutations (20%) among the affected patients. However, we also found point mutations including 1 nonsense (20%), 3 frameshifts (60%), and 1 splice sites (20%) mutations in the rest 5 patients. Among the 15 cases of exon deletion or duplication mutations, 7 were inherited from the mother, 3 were de-novo, while the other 5 were not tested. Besides, all 5 point-mutation cases were inherited from the mother, among which 4 point mutations were identified for the first time and linked to the disease phenotype. ConclusionsWe provided clinical portraits, genetic results, and the molecular effects of mutations in patients. Four novel point mutations were identified for the first time and associated with the development of DMD and BMD. Further, we expanded knowledge of the DMD variant spectrum and exemplified the emerging therapies in muscular dystrophy.

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