51
|
Bidichandani SI, Lanyon WG, Shiach CR, Lowe GD, Connor JM. Detection of mutations in ectopic factor VIII transcripts from nine haemophilia A patients and the correlation with phenotype. Hum Genet 1995; 95:531-8. [PMID: 7759074 DOI: 10.1007/bf00223865] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Haemophilia A is a common X-linked recessive disorder of bleeding caused by deleterious mutations in the gene for clotting factor VIII. The large size of the factor VIII gene, the high frequency of de novo mutations and its tissue-specific expression complicate the detection of mutations. We have used a combination of reverse transcription/polymerase chain reaction (RT-PCR) of ectopic factor VIII transcripts and PCR of genomic DNA to amplify the entire essential sequence of the factor VIII gene. Chemical mismatch cleavage analysis and direct sequencing have then be employed in order to facilitate a comprehensive search for mutations. In this report, we describe the characterisation of nine potentially pathogenic mutations, six of which are novel. The mutations include six single base substitutions (five missense, viz. D56E, V162M, G701D, A1834T and R1869I, and one nonsense, viz. R-5X), a single base deletion (5697delC), a gross deletion of exon 16 and one mRNA abnormality characteristic of the common intron-22-embedded F8A-mediated DNA inversion. In each case, a correlation of the genotype with the observed phenotype is presented. In order to evaluate the pathogenicity of the five missense mutations, we have analysed them for evolutionary sequence conservation and for their involvement with sequence motifs catalogued in the PROSITE database of protein sites and patterns. Analysis of the sequences in the immediate vicinity of the mutations has revealed sequence features that may have had a possible role in mutagenesis.
Collapse
|
52
|
Purandare SM, Lanyon WG, Arngrimsson R, Connor JM. Characterisation of a novel splice donor mutation affecting position +1 in intron 18 of the NF-1 gene. Hum Mol Genet 1995; 4:767-8. [PMID: 7633431 DOI: 10.1093/hmg/4.4.767] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
|
53
|
|
54
|
Symonds RP, Clark BJ, George WD, Bryant PE, Liu N, Connor JM. Thrombocytopenia with absent radii (TAR) syndrome: a new increased cellular radiosensitivity syndrome. Clin Oncol (R Coll Radiol) 1995; 7:56-8. [PMID: 7727311 DOI: 10.1016/s0936-6555(05)80640-5] [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: 01/26/2023]
Abstract
A 70-year-old woman with congenital absence of both radii but preservation of the thumb developed a marked pancytopenia after two i.v. injections of 1 g of 5-fluorouracil (5-FU) 1 week apart. She developed bloody diarrhoea after nine fractions of 2 Gy to parallel opposed 16 x 15 cm abdominal fields. This unusual response prompted an investigation of the radiosensitivity of the patient's cells by the sensitive G2 assay of transformed lymphocytes. The radiosensitivity of the patient's lymphoblastoid line appeared to be intermediate between that of normal individuals and an ataxia telangiectasia line. The clinical response and in vitro radiosensitivity testing suggest that the thrombocytopenia with absent radii (TAR) syndrome appears to be one of the inherited impaired DNA repair syndromes and is a very newly described radiation sensitivity syndrome. The development of three separate primary cancers in this patient (small bowel, ovary and bladder) suggests there is an increased risk of neoplasia in this condition.
Collapse
|
55
|
Tuddenham EG, Schwaab R, Seehafer J, Millar DS, Gitschier J, Higuchi M, Bidichandani S, Connor JM, Hoyer LW, Yoshioka A. Haemophilia A: database of nucleotide substitutions, deletions, insertions and rearrangements of the factor VIII gene, second edition. Nucleic Acids Res 1994; 22:4851-68. [PMID: 7984443 PMCID: PMC308545 DOI: 10.1093/nar/22.22.4851] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
A large number of different mutations in the factor VIII (F8) gene have been identified as a cause of haemophilia A. This compilation lists known single base-pair substitutions, deletions and insertions in the F8 gene and reviews the status of the inversional events which account for a substantial proportion of mutations causing severe haemophilia A.
Collapse
|
56
|
Chu CE, Donaldson MD, Kelnar CJ, Smail PJ, Greene SA, Paterson WF, Connor JM. Possible role of imprinting in the Turner phenotype. J Med Genet 1994; 31:840-2. [PMID: 7853366 PMCID: PMC1016655 DOI: 10.1136/jmg.31.11.840] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
We have attempted to investigate the role of imprinting in the phenotype of Turner's syndrome. Sixty-three patients were investigated for parental origin of the retained normal X chromosome; 43 were found to retain the maternal X (XM) and 20 the paternal (XP). The relationship between a child's pretreatment height centile and parental height centiles was examined in 36 patients. No significant correlation was found between child and parental height centiles for XP or child and paternal height centiles for XM (p > 0.05) but a strong correlation was found between child's height centile and maternal height centile (p < 0.01) for XM. Using pooled data from this and other studies there was no significant correlation with renal anomalies but a strong correlation between cardiovascular abnormalities and XM (0.01 > p > 0.001) and neck webbing and XM (p < 0.05). We conclude that imprinting may play a part in the Turner's syndrome phenotype, especially with respect to pretreatment height, cardiovascular anomalies, and neck webbing.
Collapse
|
57
|
Chu CE, Cooke A, Stephenson JB, Tolmie JL, Clarke B, Parry-Jones WL, Connor JM, Donaldson MD. Diagnosis in Prader-Willi syndrome. Arch Dis Child 1994; 71:441-2. [PMID: 7826116 PMCID: PMC1030061 DOI: 10.1136/adc.71.5.441] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Thirty one patients with the putative diagnosis of Prader-Willi syndrome were reassessed clinically and by DNA analysis. Eleven patients were judged not to have Prader-Willi syndrome and 20 to have the condition. This was confirmed by DNA analysis in all but one case. The diagnosis of Prader-Willi syndrome, especially in early infancy, should be made with caution unless confirmed by molecular genetic studies.
Collapse
|
58
|
Bidichandani SI, Lanyon WG, Connor JM. Characterisation of a 5-bp deletion in exon 4 of the factor VIII gene: concordance with slipped-mispairing at DNA replication. Hum Genet 1994; 94:447-9. [PMID: 7927348 DOI: 10.1007/bf00201612] [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: 01/27/2023]
Abstract
In an attempt to characterize disease producing mutations in the factor VIII gene we screened exons 4, 7, 8, 11, 12 and 16 by PCR-SSCP (polymerase chain reaction-single strand conformation polymorphism), in 12 randomly selected haemophilia A patients. These exons were chosen because they have been reported to harbour a disproportionately high number of mutations relative to their size. Using this strategy we detected a frame-shifting 5-bp deletion (TACCT, involving nucleotides 519-523), which is predicted to result in a severely truncated factor VIII polypeptide, terminating approximately midway through the conserved A1 domain and resulting in the observed severe phenotype. We also showed that the sequence in the vicinity of the observed deletion is concordant with the modified "slipped-mispairing at DNA replication" model of Krawczak and Cooper.
Collapse
|
59
|
Tuddenham EG, Schwaab R, Seehafer J, Millar DS, Gitschier J, Higuchi M, Bidichandani S, Connor JM, Hoyer LW, Yoshioka A. Haemophilia A: database of nucleotide substitutions, deletions, insertions and rearrangements of the factor VIII gene, second edition. Nucleic Acids Res 1994; 22:3511-33. [PMID: 7937051 PMCID: PMC308313 DOI: 10.1093/nar/22.17.3511] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
A large number of different mutations in the factor VIII (F8) gene have been identified as a cause of haemophilia A. This compilation lists known single base-pair substitutions, deletions and insertions in the F8 gene and reviews the status of the inversional events which account for a substantial proportion of mutations causing severe haemophilia A.
Collapse
|
60
|
Spencer K, Aitken DA, Crossley JA, McCaw G, Berry E, Anderson R, Connor JM, Macri JN. First trimester biochemical screening for trisomy 21: the role of free beta hCG, alpha fetoprotein and pregnancy associated plasma protein A. Ann Clin Biochem 1994; 31 ( Pt 5):447-54. [PMID: 7530437 DOI: 10.1177/000456329403100504] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The potential efficacy of screening for trisomy 21 in the first trimester, using maternal serum markers alpha fetoprotein, free beta human chorionic gonadotropin, unconjugated oestriol and pregnancy associated plasma protein A, was studied in an unselected population of women between the seventh and fourteenth week of gestation. Using a combination of alpha fetoprotein and free beta human chorionic gonadotropin, 53% of affected pregnancies could be identified at a false positive rate of 5%. Unconjugated oestriol and pregnancy associated plasma protein A levels were lower in cases of trisomy 21, but their inclusion with other markers did not significantly improve detection rate. Monitoring the same pregnancies also in the second trimester showed that screening in the first trimester identified the same cases as in the second. We conclude that first trimester screening using free beta human chorionic gonadotropin and alpha fetoprotein, is a viable possibility and will lead to detection rates in excess of 50%. Prospective studies are needed to confirm these observations.
Collapse
|
61
|
Purandare SM, Lanyon WG, Connor JM. Characterisation of inherited and sporadic mutations in neurofibromatosis type-1. Hum Mol Genet 1994; 3:1109-15. [PMID: 7981679 DOI: 10.1093/hmg/3.7.1109] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Neurofibromatosis type-1 (NF-1) is an autosomal dominant disorder, caused by mutations in the NF-1 gene. Mutation analysis in the NF-1 gene is complicated by the large size of the gene, the high mutation rate, and the presence of pseudogenes. By means of the polymerase chain reaction, we have amplified 70% of the NF-1 coding sequence using reverse transcribed mRNA and genomic DNA from 25 unrelated Scottish Caucasian patients. We have used chemical mismatch cleavage analysis and direct sequencing of asymmetrically amplifed PCR products to characterise mutations within the NF-1 gene. Using the above strategy, we detected 10 novel mutations and an intragenic polymorphism with a heterozygosity of approximately 47% in the Scottish population. Of the 10 mutations, 7 are potentially disease causing. They include splice site errors responsible for exon skipping (1721 + 3A to G) and (5749 + 2T to G), small insertions (7485insGG) and (6519insG), a nonsense mutation (R2496X), and missense and silent mutations (G1166D, K1419R, G1404G, S1311S, N1776N). A correlation of the phenotype with the genotype is presented. Thus, in this study we have identified a heterogeneous group of germline mutations, the majority of which are predicted to cause disruption of the protein product, neurofibromin. This approach has therefore proved to be useful for the detection of mutations in the gene for neurofibromatosis type-1, and can be applied to detection of molecular pathologies in general.
Collapse
|
62
|
Crossley JA, Aitken DA, Berry E, Connor JM. Impact of a regional screening programme using maternal serum alpha fetoprotein (AFP) and human chorionic gonadotrophin (hCG) on the birth incidence of Down's syndrome in the west of Scotland. J Med Screen 1994; 1:180-3. [PMID: 8790513 DOI: 10.1177/096914139400100309] [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: 02/02/2023]
Abstract
OBJECTIVES To evaluate the impact of a large scale population screening programme on the birth incidence of Down's syndrome in the west of Scotland over a 12 month period. METHODS Biochemical screening for Down's syndrome using maternal serum alpha fetoprotein, chorionic gonadotrophin, and maternal age was offered to a pregnant population of 37,226 women in the west of Scotland between 1991 and 1992. The combined risk of Down's syndrome pregnancy was reported for each of the 30,084 women who opted for screening. RESULTS When a threshold risk of 1:220 was used 1523 women (5.1% of the screened population) were assigned to the high risk group, of whom 1070 (70%) proceeded to diagnostic amniocentesis or midtrimester chorionic villus sampling. When multiple sources of ascertainment were used 37 Down's syndrome pregnancies were identified within the screened population, 26 (70%) of which were within the high risk group and 21 (57%) of which were prenatally diagnosed. In addition, three Down's syndrome pregnancies were diagnosed by first trimester chorionic villus sampling before biochemical screening. A further 10 Down's syndrome pregnancies were identified at birth, eight to women who had not had a screening test and two to women who had moved into the area, making a total of 50 Down's syndrome pregnancies in the whole pregnant population of 37,226. Thus the potential prenatal detection rate in the screened population was 70% (26/37), the actual prenatal detection rate in the screened population was 57% (21/37), and the overall prenatal detection rate in the total (screened and unscreened) population was 48% (24/50). CONCLUSION Biochemical screening for Down's syndrome is practical and effective in routine clinical practice, enabling women to make an informed choice about prenatal diagnosis and providing better use of scarce resources when a suitable protocol is applied to the whole pregnant population. Its maximum potential for the reduction of the birth incidence of Down's syndrome is limited by incomplete uptake of screening and compliance with diagnostic testing in the high risk group.
Collapse
|
63
|
Arngrimsson R, Connor JM, Geirsson RT, Brennecke S, Cooper DW. Is genetic susceptibility for pre-eclampsia and eclampsia associated with implantation failure and fetal demise? Lancet 1994; 343:1643-4. [PMID: 7911952 DOI: 10.1016/s0140-6736(94)93101-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
|
64
|
Morrison N, Sellar RE, Boyd E, Eidne KA, Connor JM. Assignment of the gene encoding the human gonadotropin-releasing hormone receptor to 4q13.2-13.3 by fluorescence in situ hybridization. Hum Genet 1994; 93:714-5. [PMID: 8005601 DOI: 10.1007/bf00201579] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
|
65
|
Morrison N, Duthie SM, Boyd E, Eidne KA, Connor JM. Assignment of the gene encoding the human thyrotropin-releasing hormone receptor to 8q23 by fluorescence in situ hybridization. Hum Genet 1994; 93:716-8. [PMID: 8005602 DOI: 10.1007/bf00201580] [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: 01/28/2023]
Abstract
A cDNA for human thyrotropin-releasing hormone (TRH) receptor has been isolated from a human pituitary cDNA library. By using this cDNA as a biotinylated probe, the gene encoding the TRH receptor has been localized to chromosome 8q23 by in situ hybridization.
Collapse
|
66
|
Mgone CS, Lanyon WG, Moore MR, Louie GV, Connor JM. Identification of five novel mutations in the porphobilinogen deaminase gene. Hum Mol Genet 1994; 3:809-11. [PMID: 8081367 DOI: 10.1093/hmg/3.5.809] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
We have studied the porphobilinogen deaminase gene transcripts from seven unrelated patients from the West of Scotland, all suffering from acute intermittent porphyria. This was achieved by reverse transcription and PCR amplification of mRNA followed by asymmetric amplification and direct sequencing. Five novel and two previously described mutations were identified and found to be single base substitutions. Of the five novel mutations, three were missense (R116Q, T2691, G274R) and two were nonsense (Q204 Stop, W283 Stop). Using Escherichia coli PBGD as a model, it is possible to predict and explain the deleterious effects that these mutations might have on the function and structure of the enzyme.
Collapse
|
67
|
Jamieson ME, Coutts JR, Connor JM. The chromosome constitution of human preimplantation embryos fertilized in vitro. Hum Reprod 1994; 9:709-15. [PMID: 8046027 DOI: 10.1093/oxfordjournals.humrep.a138575] [Citation(s) in RCA: 84] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The chromosome constitution of five haploid, 178 diploid and 11 triploid embryos fertilized in vitro was determined after fixation on day 2 or day 3 of development. Karyotype analysis of 178 diploid embryos revealed abnormalities in 40 (22.5%) cases: 34 (19.1%) aneuploids, four (2.2%) mosaic embryos and two (1.1%) structural anomalies were identified. The majority of aneuploid karyotypes (28/34) involved a single chromosome but six embryos had aneuploidy of two or three chromosomes. The E group was most frequently involved in aneuploid karyotypes (10/23 hyperdiploid embryos) and trisomy 16, the most common single anomaly in diploid embryos, was detected in 2.2% (4/178) of cases. Only one case of sex chromosome monosomy was identified. An excess of female karyotypes was detected in abnormal cases (sex ratio 0.48); this ratio was significantly (P < 0.05) different from that observed in normal cases (74:64, XY:XX). The incidence of aneuploidy increased with maternal age but this did not reach statistical significance. Embryo morphology and growth rate, assessed by embryo development rating (EDR), did not distinguish between normal (mean score 7.9; mean EDR 96.1) and aneuploid (mean score 8.1; mean EDR, 92.1) embryos. Numbers of hyperploid (n = 17) and hypoploid (n = 11) embryos (non-mosaic cases involving single chromosomes) were not statistically different. The relative proportions of chromosomes involved in trisomic karyotypes showed a remarkable similarity to the pattern in spontaneous abortions. Pronuclear status was an unreliable predictor of ploidy. Small numbers of karyotyped triploid embryos revealed equal proportions of XXX, XXY and XYY embryos.
Collapse
|
68
|
Bidichandani SI, Shiach CR, Lanyon WG, Connor JM. A novel splice donor mutation affecting position +3 in intron 6 of the factor VIII gene. Hum Mol Genet 1994; 3:651-3. [PMID: 8069313 DOI: 10.1093/hmg/3.4.651] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
|
69
|
Elshafey A, Lanyon WG, Connor JM. Identification of a new missense point mutation in exon 4 of the Cu/Zn superoxide dismutase (SOD-1) gene in a family with amyotrophic lateral sclerosis. Hum Mol Genet 1994; 3:363-4. [PMID: 8004110 DOI: 10.1093/hmg/3.2.363] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
|
70
|
Purandare SM, Davidson HR, Lanyon WG, Connor JM. A novel insertional mutation of a single base in exon 34 of the neurofibromatosis-1 gene. Hum Mutat 1994; 3:76-8. [PMID: 8118468 DOI: 10.1002/humu.1380030116] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
|
71
|
Mgone CS, Lanyon WG, Moore MR, Louie GV, Connor JM. Detection of a high mutation frequency in exon 12 of the porphobilinogen deaminase gene in patients with acute intermittent porphyria. Hum Genet 1993; 92:619-22. [PMID: 8262523 DOI: 10.1007/bf00420949] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Direct cDNA sequencing was performed on asymmetrically amplified transcripts from the porphobilinogen deaminase (PBG-D) gene of thirteen unrelated individuals with acute intermittent porphyria. Four different mutations and a polymorphic site were detected in exon 12 of the gene, four being the result of single base substitutions and one being caused by dinucleotide deletion. All of these mutations are located in domain 3 of the PBG-D molecule, with the single base substitutions affecting the hydrophobic interfaces between domains 1 and 3. The dinucleotide deletion results in a frame-shift producing a premature stop codon.
Collapse
|
72
|
Aitken DA, McCaw G, Crossley JA, Berry E, Connor JM, Spencer K, Macri JN. First-trimester biochemical screening for fetal chromosome abnormalities and neural tube defects. Prenat Diagn 1993; 13:681-9. [PMID: 8284287 DOI: 10.1002/pd.1970130804] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Alpha-fetoprotein (AFP), unconjugated oestriol (UE3), intact human chorionic gonadotrophin (intHCG), and the free beta subunit of chorionic gonadotrophin (F beta HCG) were investigated in a series of 21 chromosomally abnormal and 14 open neural tube defect pregnancies ascertained from a series of 14,000 prospectively collected maternal serum samples at 6-14 weeks' gestation. In 16 cases of Down's syndrome, significant reductions were found for AFP (0.65 multiples of the normal median) and UE3 (0.67 MOM). IntHCG levels were unaltered (0.97 MOM) but a significant increase was found for F beta HCG (1.96 MOM). Significant correlations were found for AFP and UE3 in the controls and for intHCG and F beta HCG in both the control and the Down's syndrome pregnancies. In a group of five trisomy 18 pregnancies, median MOMs were for AFP 0.71, for UE3 0.34, for intHCG 0.27, and for F beta HCG 0.15. None of 13 pregnancies with open neural tube defects at 8-13 weeks gestation had elevated maternal serum AFP levels, whereas matched second-trimester samples from the same pregnancies at 16-18 weeks gestation all had significantly elevated AFP levels. Thus, biochemical screening for chromosome abnormalities may be practicable in the first trimester using free beta human chorionic gonadotrophin in combination with AFP and maternal age. However, a separate screening protocol using AFP at 15-18 weeks gestation would still be required for effective detection of neural tube defects.
Collapse
|
73
|
Connor JM. Isolation, Migration and Health. Br J Soc Med 1993. [DOI: 10.1136/jech.47.4.338-b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
74
|
Connor JM, Skirton H, Lunt PW. A three generation family with fibrodysplasia ossificans progressiva. J Med Genet 1993; 30:687-9. [PMID: 8411056 PMCID: PMC1016500 DOI: 10.1136/jmg.30.8.687] [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: 01/30/2023]
Abstract
A family with five persons affected with fibrodysplasia ossificans progressiva (myositis ossificans progressiva) in three generations is described. This is the first well documented three generation family with this condition and provides further evidence for autosomal dominant inheritance. A wide range of phenotypic severity is apparent, from disabling ectopic bone formation and premature death to an asymptomatic adult with characteristic big toe malformations.
Collapse
|
75
|
Arngrimsson R, Dokal I, Luzzatto L, Connor JM. Dyskeratosis congenita: three additional families show linkage to a locus in Xq28. J Med Genet 1993; 30:618-9. [PMID: 8105085 PMCID: PMC1016470 DOI: 10.1136/jmg.30.7.618] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Dyskeratosis congenita (DC) is a rare inherited disorder with most families being of the X linked recessive type. We describe three families which show linkage to the marker DXS52 on Xq28. The combined maximum lod score was 2.00 at zero recombination. This is further evidence that the X linked DC gene is located at Xq28 and brings the reported maximum lod score for DC and DXS52 to 5.33 at zero recombination fraction, with a supporting recombination fraction interval of 0.00-0.10.
Collapse
|