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Lagerström-Fermér M, Sundvall M, Johnsen E, Warne GL, Forrest SM, Zajac JD, Rickards A, Ravine D, Landegren U, Pettersson U. X-linked recessive panhypopituitarism associated with a regional duplication in Xq25-q26. Am J Hum Genet 1997; 60:910-6. [PMID: 9106538 PMCID: PMC1712462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
We present a linkage analysis and a clinical update on a previously reported family with X-linked recessive panhypopituitarism, now in its fourth generation. Affected members exhibit variable degrees of hypopituitarism and mental retardation. The markers DXS737 and DXS1187 in the q25-q26 region of the X chromosome showed evidence for linkage with a peak LOD score (Zmax) of 4.12 at zero recombination fraction (theta(max) = 0). An apparent extra copy of the marker DXS102, observed in the region of the disease gene in affected males and heterozygous carrier females, suggests that a segment including this marker is duplicated. The gene causing this disorder appears to code for a dosage-sensitive protein central to development of the pituitary.
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Distante S, Nasioulas S, Somers GR, Cameron DJ, Young MA, Forrest SM, Gardner RJ. Familial adenomatous polyposis in a 5 year old child: a clinical, pathological, and molecular genetic study. J Med Genet 1996; 33:157-60. [PMID: 8929955 PMCID: PMC1051844 DOI: 10.1136/jmg.33.2.157] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
A girl aged 5 years 8 months presented with rectal bleeding; her father had had familial adenomatous polyposis (FAP) and a colectomy at the age of 23. Endoscopy showed extensive polyposis and she had a colectomy. The proband and her father had the common codon 1309 5 bp deletion APC mutation. This mutation predisposes to early onset of FAP, and consideration needs to be given to having molecular testing of at risk members of these families done in childhood.
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Slater H, Shaw JH, Bankier A, Forrest SM, Dawson G. UPD 13: no indication of maternal or paternal imprinting of genes on chromosome 13. J Med Genet 1995; 32:493. [PMID: 7666408 PMCID: PMC1050497 DOI: 10.1136/jmg.32.6.493] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Slater H, Shaw JH, Dawson G, Bankier A, Forrest SM. Maternal uniparental disomy of chromosome 13 in a phenotypically normal child. J Med Genet 1994; 31:644-6. [PMID: 7815424 PMCID: PMC1050029 DOI: 10.1136/jmg.31.8.644] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A case of maternal uniparental disomy of chromosome 13 is described. The subject is a phenotypically normal male who inherited a t(13;13)(p11.2;p11.2) from his mother who is a carrier of this translocation. The mother was ascertained through a history of recurrent abortion and is phenotypically normal. The translocation in both subjects was studied by cytogenetic and DNA analysis and appears to be a true dicentric isochromosome. These findings show that maternal uniparental disomy of chromosome 13 has had no pathological consequences and suggests that there is no imprinting of genes on maternally derived chromosome 13.
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Ramus SJ, Forrest SM, Pitt DB, Saleeba JA, Cotton RG. Comparison of genotype and intellectual phenotype in untreated PKU patients. J Med Genet 1993; 30:401-5. [PMID: 8320703 PMCID: PMC1016377 DOI: 10.1136/jmg.30.5.401] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We have screened 55 untreated phenylketonuria patients from 42 families for common mutations of the phenylalanine hydroxylase gene and determined both causative alleles in 12 families. The correlation between genotype and intellectual phenotype of patients in these families was examined. Our results were compared to a study which predicted phenylalanine hydroxylase activity based on genotype and examined its correlation with the biochemical phenotype of treated patients. Some of the intellectual phenotypes of patients in our study correlated well with the predicted activities. However, we found one family with a genotype expected to have no activity of phenylalanine hydroxylase where the patients were not severely retarded. Major differences in intellectual phenotype were found in patients with the same genotype both between unrelated subjects and within families, suggesting that there is not a simple correlation between genotype and intellectual phenotype.
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Ravine D, Walker RG, Gibson RN, Forrest SM, Richards RI, Friend K, Sheffield LJ, Kincaid-Smith P, Danks DM. Phenotype and genotype heterogeneity in autosomal dominant polycystic kidney disease. Lancet 1992; 340:1330-3. [PMID: 1360045 DOI: 10.1016/0140-6736(92)92503-8] [Citation(s) in RCA: 118] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
It is now clear that mutations of at least two genetic loci can lead to autosomal dominant polycystic kidney disease (ADPKD). We have compared the clinical features of ADPKD caused by mutations at the PKD1 locus (linked to the alpha-globin complex on chromosome 16) with those of disease not linked to the locus (non-PKD1). We identified 18 families (285 affected members) with mutations at PKD1 and 5 families (49 affected individuals) in which involvement of this locus could be dismissed. Non-PKD1 patients lived longer than PKD1 patients (median survival 71.5 vs 56.0 years), had a lower risk of progressing to renal failure (odds ratio 0.35, 95% CI 0.13-0.92), were less likely to have hypertension (odds ratio adjusted for age and family of origin 0.29, 0.11-0.80), were diagnosed at an older age (median 69.1 vs 44.8 years), and had fewer renal cysts at the time of diagnosis. Although most of the PKD1 families were ascertained through clinics treating patients with renal impairment, no non-PKD1 family was identified through this source. Non-PKD1 ADPKD has a much milder phenotype than that linked to PKD1. Partly as a result of this difference in severity, the reported prevalence of this genotype is probably an underestimate.
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Ramus SJ, Forrest SM, Saleeba JA, Cotton RG. CpG hotspot causes second mutation in codon 408 of the phenylalanine hydroxylase gene. Hum Genet 1992; 90:147-8. [PMID: 1358783 DOI: 10.1007/bf00210760] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
A new mutation has been identified in exon 12 of the gene encoding phenylalanine hydroxylase at codon 408. The single base change from guanine to adenine changes the amino acid arginine to glutamine; thus, the mutation is defined as R408Q. This codon is the site of a mutation known to causes phenylketonuria. Both these mutations are located at the same CpG site.
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Smith SH, Forrest SM, Williams DC, Cabell MF, Acquavella MF, Abelt CJ. Regioselectivity of the insertion reactions of some aromatic diazo compound complexes with cyclomaltoheptaose. Carbohydr Res 1992; 230:289-97. [PMID: 1394302 DOI: 10.1016/0008-6215(92)84039-u] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Pyrolysis of solid complexes of aromatic diazo compounds with cyclomaltoheptaose (beta-cyclodextrin) yields either derivatives via insertion of carbene into hydroxyl groups. The distribution of the 2-, 3-, and 6-O-isomers indicates that the regioselectivity is moderate. The guest geometry is not as important as its size in determining the ratios of regioisomers. The origins of the regioselectivity are discussed.
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Forrest SM, Dry PJ, Cotton RG. Use of the chemical cleavage of mismatch method for prenatal diagnosis of alpha-1-antitrypsin deficiency. Prenat Diagn 1992; 12:133-7. [PMID: 1553359 DOI: 10.1002/pd.1970120209] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The most common mutation in alpha-1-antitrypsin deficiency, conversion of a G to an A at base 9989 (PI-Z), was detected with the chemical cleavage of mismatch method, demonstrating the power of the method for prenatal diagnosis. Exon V of the gene was amplified using the polymerase chain reaction and heteroduplexes were formed to test for the presence of the mutation. The predicted C mismatch was readily detectable with hydroxylamine, and by making the probe from the chorionic villus sample it was possible to determine that the fetus was heterozygous, not homozygous, for the mutation.
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Ramus SJ, Forrest SM, Cotton RG. Illegitimate transcription of phenylalanine hydroxylase for detection of mutations in patients with phenylketonuria. Hum Mutat 1992; 1:154-8. [PMID: 1301202 DOI: 10.1002/humu.1380010211] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Illegitimately transcribed phenylalanine hydroxylase mRNA was amplified using the polymerase chain reaction from both fibroblasts and Epstein-Barr virus-transformed lymphocytes. This method was used to study mutations of this gene in patients with phenylketonuria and known point mutations were easily detected. Illegitimate transcription was successful for studying splicing defects and it was found that the previously described mutation which changes G to A at the 5' donor site of intron 7 causes exon 7 to be spliced out.
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36
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Dianzani I, Camaschella C, Saglio G, Forrest SM, Ramus S, Cotton RG. Simultaneous screening for beta-thalassemia mutations by chemical cleavage of mismatch. Genomics 1991; 11:48-53. [PMID: 1765385 DOI: 10.1016/0888-7543(91)90100-s] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We used the chemical cleavage of mismatch (CCM) method to screen the beta-globin gene simultaneously for Mediterranean beta-thalassemia mutations. The beta-globin gene was amplified in two segments encompassing the whole gene and hybridized to a corresponding labeled PCR product from a normal subject. All the known mutations tested were identified and discriminated. Three beta-thalassemic subjects with previously undiagnosed mutations were identified as carriers of two rare DNA changes. The inheritance of the mutations could be traced in family studies, showing the reliability of the method even for prenatal diagnosis. The beta-globin gene polymorphisms were also detected and the framework was determined for most alleles. Our results suggest further applicability of the CCM method as a means to screen a gene simultaneously for multiple mutations.
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Forrest SM, Dahl HH, Howells DW, Dianzani I, Cotton RG. Mutation detection in phenylketonuria by using chemical cleavage of mismatch: importance of using probes from both normal and patient samples. Am J Hum Genet 1991; 49:175-83. [PMID: 2063869 PMCID: PMC1683212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
mRNA from a postmortem liver sample of a patient with classical phenylketonuria was examined using the chemical cleavage of mismatch (CCM) method to search for mutations in phenylalanine hydroxylase. Initial screening identified a heterozygous alteration in exon 2 which changed the encoded amino acid from phenylalanine (TTC) to leucine (TTG) at codon 39 and a polymorphism at codon 430 where the change from CTG to CTC did not alter the encoded leucine. Use of the CCM technique also revealed that the control reference clone differed from the published sequence by having a substitution of isoleucine (ATT) for methionine (ATG) at codon 276 and CAA rather than CAG as the codon for glutamine 232. By using the mRNA from the patient instead of the control as the source for the radiolabeled probe for the CCM technique, a second previously undetected alteration was identified in exon 10 where the change from TCA to CCA at codon 349 altered the amino acid from serine to arginine. Judicious choice of probes gives the CCM method the potential to detect close to 100% of single base mutations.
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38
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Dahl HH, Hutchison WM, Guo Z, Forrest SM, Hansen LL. Polymorphisms in the human X-linked pyruvate dehydrogenase E1 alpha gene. Hum Genet 1991; 87:49-53. [PMID: 1674716 DOI: 10.1007/bf01213091] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Pyruvate dehydrogenase E1 alpha deficiency is an X-chromosome-linked disorder, often with fatal consequences. We have searched for genetically useful polymorphisms in or near this gene. No restriction fragment length polymorphisms were detected using a battery of 36 different restriction enzymes and probing with a full-length cDNA fragment, or two single-copy genomic fragments located within intron 8, and 15 kb 3' of the coding region, respectively. The chemical cleavage method was then applied to the detection of base changes in or near the gene. One polymorphism was found in exon 8 of the coding region. However, no base changes were detected in intron 3 or in the part of intron 8 covered by fragment gB2. Three blocks of microsatellite DNA containing variable numbers of CA-repeats were isolated from the 5' end of the gene and characterized. Length polymorphisms in these microsatellite DNAs were analysed using the polymerase chain reaction. Although the three loci are tightly linked, the polymorphisms appear not to be in disequilibrium, making them useful markers in linkage studies of the pyruvate dehydrogenase E1 alpha gene. Of 31 females analysed 12(39%) were heterozygous for at least one length polymorphism of the three (CA)n alleles.
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Dianzani I, Forrest SM, Camaschella C, Saglio G, Ponzone A, Cotton RG. Screening for mutations in the phenylalanine hydroxylase gene from Italian patients with phenylketonuria by using the chemical cleavage method: a new splice mutation. Am J Hum Genet 1991; 48:631-5. [PMID: 1671810 PMCID: PMC1682973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
To investigate the molecular basis of phenylketonuria in Italy we applied the chemical cleavage method (CCM) on amplified DNA encompassing exons 7 and 8 of the phenylalanine hydroxylase gene. These exons are in a region likely to be involved in enzyme function. Using this approach, we could simultaneously screen for novel mutations and for seven reported mutations which map in this area. Three mutations were identified. The first was shown to be a not previously described mutation: a G----A substitution at the 5' donor junction splice site of intron 7. The second change was a reported G----A mutation at codon 261. The third change corresponded to a polymorphism at codon 245. Our results indicate that CCM analysis of amplified genomic DNA fragments can be successfully used to search for mutations in large genes whose transcripts are not readily available.
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Dianzani I, Forrest SM, Camaschella C, Gottardi E, Cotton RG. Heterozygotes and homozygotes: discrimination by chemical cleavage of mismatch. Am J Hum Genet 1991; 48:423-4. [PMID: 1990848 PMCID: PMC1683021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
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41
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Love DR, Flint TJ, Marsden RF, Bloomfield JF, Daniels RJ, Forrest SM, Gabrielli O, Giorgi P, Novelli G, Davies KE. Characterization of deletions in the dystrophin gene giving mild phenotypes. AMERICAN JOURNAL OF MEDICAL GENETICS 1990; 37:136-42. [PMID: 2240031 DOI: 10.1002/ajmg.1320370132] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We have characterized deletions of the dystrophin gene in patients suffering from relatively mild muscular dystrophy. Our data show that most of the Becker muscular dystrophy (BMD) patients have intragenic deletions which leave the protein reading frame in phase. Remarkably, large deletions of the region corresponding to the central triple helical repeats in the protein can result in an exceptionally mild phenotype. Three brothers suffering from BMD, glycerol kinase deficiency, and adrenal hypoplasia possess a deletion at the 3' end of the gene. They also display developmental delay. Thus the 3' processing of the gene must be necessary for the correct function of the dystrophin molecule.
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42
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Howells DW, Forrest SM, Dahl HH, Cotton RG. Insertion of an extra codon for threonine is a cause of dihydropteridine reductase deficiency. Am J Hum Genet 1990; 47:279-85. [PMID: 2116088 PMCID: PMC1683733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The mutation in a patient with dihydropteridine reductase deficiency has been located and characterized. Polymerase chain reaction (PCR) was used to amplify the coding sequence of human dihydropteridine reductase from the messenger RNA of skin fibroblasts. Chemical cleavage of mismatches indicated a mismatched thymine and cytosine at approximately 117 and 147 bases, respectively, from the end of the probe. Cloning and sequencing of the mutant PCR products revealed the insertion of the triplet ACT (threonine), after alanine 122 (base 390). Amplification of a small region around this mutation by using genomic DNA as the PCR target indicates that the mutation is completely within an exon. Unequal crossing-over at the second base in the preceding alanine codon and duplication of the bases CTA may be the mechanism of mutagenesis. The cleavage site 147 bases from the end of the probe corresponded to the conversion of guanine to adenine at base 420 (CTG to CTA) and does not alter the code for leucine. This change, which was also seen in another dihydropteridine reductase-deficient child and in a control subject probably represents a common neutral polymorphism.
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England SB, Nicholson LV, Johnson MA, Forrest SM, Love DR, Zubrzycka-Gaarn EE, Bulman DE, Harris JB, Davies KE. Very mild muscular dystrophy associated with the deletion of 46% of dystrophin. Nature 1990; 343:180-2. [PMID: 2404210 DOI: 10.1038/343180a0] [Citation(s) in RCA: 425] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD), a much milder form of the disease where the age of onset can sometimes be as late as the third or fourth decade of life, are caused by mutations in the same X-linked gene, a 14 kilobase (kb) transcript which is spread over more than 2 megabases of the human X chromosome. The corresponding protein, dystrophin, has a relative molecular mass of 400,000. Most mutations causing DMD and BMD are deletions and deletions associated with both phenotypes are observed throughout the gene sequence. This observation led to the suggestion that DMD patients possess deletions that disrupt the reading frame of the protein, whereas BMD patients have deletions that retain the translational reading frame and enable the muscle cells to produce altered dystrophin products. This theory is supported by immunoblotting studies, which show that DMD patients lack dystrophin in their muscle cells or that dystrophin is present at very low levels, whereas BMD patients produce a protein with reduced abundance or abnormal size. Here we describe a deletion of the dystrophin gene in a family segregating for very mild BMD, one member of which was still ambulant at age 61 years, which removes a central part of the dystrophin gene encompassing 5,106 base pairs of coding sequence, almost half the coding information. Immunological analysis of muscle from one of the patients demonstrates that this mutation results in the production of a truncated polypeptide localized correctly in the muscle cell. These results are particularly significant in the context of gene therapy which, if it is ever envisaged, would be facilitated by the replacement of the very large dystrophin gene with a more manipulatable mini-gene construct.
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Rosenthal A, Speer A, Billwitz H, Cross GS, Forrest SM, Davies KE. Two human cDNA molecules coding for the Duchenne muscular dystrophy (DMD) locus are highly homologous. Nucleic Acids Res 1989; 17:5391. [PMID: 2668885 PMCID: PMC318130 DOI: 10.1093/nar/17.13.5391] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
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45
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Love DR, Forrest SM, Smith TJ, England S, Flint T, Davies KE, Speer A. Molecular analysis of Duchenne and Becker muscular dystrophies. Br Med Bull 1989; 45:659-80. [PMID: 2688822 DOI: 10.1093/oxfordjournals.bmb.a072351] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The analysis of DNA from patients suffering from Duchenne (DMD) and Becker (BMD) muscular distrophies has resulted in the identification of a single gene locus for these diseases. The locus is deleted to varying extents in affected patients. The translation product of this locus has been implicated as the site of the primary biochemical defect responsible for these muscle disorders. There is no simple correlation between the severity of the clinical phenotype and the location and extent of genomic deletions in the DMD locus. This lack of correlation may be due, in part, to the difficulties inherent in examining a gene of complex arrangement, with exons distributed over a large genomic distance. This paper examines the location of deletion breakpoints in DMD and BMD patients. The molecular analysis of these deletions are presented in the context of transcriptional and translational studies of DMD gene expression and the manifestation of the clinical phenotype.
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Speer A, Rosenthal A, Billwitz H, Hanke R, Forrest SM, Love D, Davies KE, Coutelle C. DNA amplification of a further exon of Duchenne muscular dystrophy locus increase possibilities for deletion screening. Nucleic Acids Res 1989; 17:4892. [PMID: 2783234 PMCID: PMC318056 DOI: 10.1093/nar/17.12.4892] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
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47
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Cavanna JS, Coulton G, Morgan JE, Brockdorff N, Forrest SM, Davies KE, Brown SD. Molecular and genetic mapping of the mouse mdx locus. Genomics 1988; 3:337-41. [PMID: 3243547 DOI: 10.1016/0888-7543(88)90124-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
mdx is an X-linked muscular dystrophy mutant of the mouse and a putative homolog of the human X-linked muscular dystrophy locus--Duchenne muscular dystrophy (DMD). Utilizing a C57BL/10/Mus Spretus interspecific cross in which the mdx mutation was segregating, we have constructed a detailed genetic map around the mdx locus on the mouse X chromosome. We were unable to detect recombinants between mdx and exonic probes derived from the human DMD gene. These genetic data support the contention from biochemical studies (E.P. Hoffman, R. H. Brown, and L. M. Kunkel, 1987, Cell 51: 919-928) that DMD and mdx are homologous genes.
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48
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Read AP, Mountford RC, Forrest SM, Kenwrick SJ, Davies KE, Harris R. Patterns of exon deletions in Duchenne and Becker muscular dystrophy. Hum Genet 1988; 80:152-6. [PMID: 3169738 DOI: 10.1007/bf00702859] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A panel of patients with Duchenne and Becker muscular dystrophy (DMD and BMD) has been screened with the cDNA probes Cf56a and Cf23a, which detect exons in the central part of the DMD gene. One or more exons were deleted in 60% of patients. The deletions were mapped and prove to be heterogeneous in size and extent, particularly in DMD. Deletions specific to DMD and to BMD are described. Half of all BMD patients have a deletion of one particular small group of exons; smaller deletions within this same group produce the more severe DMD.
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Forrest SM, Smith TJ, Cross GS, Kenwrick SJ, England S, Flint T, Davies KE. Molecular analysis and diagnosis of Duchenne muscular dystrophy. JOURNAL OF THE ROYAL COLLEGE OF PHYSICIANS OF LONDON 1988; 22:65-7. [PMID: 3294388 PMCID: PMC5379393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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50
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Forrest SM, Cross GS, Flint T, Speer A, Robson KJ, Davies KE. Further studies of gene deletions that cause Duchenne and Becker muscular dystrophies. Genomics 1988; 2:109-14. [PMID: 3410474 DOI: 10.1016/0888-7543(88)90091-2] [Citation(s) in RCA: 135] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Fetal muscle cDNA clones covering at least 11.4 kb of the Duchenne muscular dystrophy (DMD) gene sequence were used to identify a deletion-prone region in DNA from DMD and Becker muscular dystrophy (BMD) patients. Of 36 BMD cases, 17 (47%) had deletions and all of the deletions began in the same intron of the gene. Of 107 DMD patients, 27 (25%) were deleted for this region, and 19 deletions originate in the same intron. Using a cDNA probe for an adjacent region of the gene, 32 new deletions were detected in DMD patients (total 44%). No new BMD deletions were detected. The DMD deletions were very heterogeneous. Thus two cDNA probes covering 2.4 kb could detect 53% of these deletions. Considering the whole locus, DMD and BMD are caused by a deletion of the gene sequence in at least 67% of cases.
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