A ligase-mediated gene detection technique.

PubWeight™: 7.61‹?› | Rank: Top 0.1%

🔗 View Article (PMID 3413476)

Published in Science on August 26, 1988

Authors

U Landegren1, R Kaiser, J Sanders, L Hood

Author Affiliations

1: Division of Biology, California Institute of Technology, Pasadena 91125.

Articles citing this

(truncated to the top 100)

Sequencing technologies - the next generation. Nat Rev Genet (2009) 40.57

Chromosome Conformation Capture Carbon Copy (5C): a massively parallel solution for mapping interactions between genomic elements. Genome Res (2006) 13.32

Allele-specific enzymatic amplification of beta-globin genomic DNA for diagnosis of sickle cell anemia. Proc Natl Acad Sci U S A (1989) 5.30

Genetic disease detection and DNA amplification using cloned thermostable ligase. Proc Natl Acad Sci U S A (1991) 4.89

Diversity Arrays Technology (DArT) for whole-genome profiling of barley. Proc Natl Acad Sci U S A (2004) 4.70

Automated DNA diagnostics using an ELISA-based oligonucleotide ligation assay. Proc Natl Acad Sci U S A (1990) 2.88

Genetic Bit Analysis: a solid phase method for typing single nucleotide polymorphisms. Nucleic Acids Res (1994) 2.79

Determination of single-nucleotide polymorphisms by real-time pyrophosphate DNA sequencing. Genome Res (2000) 2.69

A method for high-throughput gene expression signature analysis. Genome Biol (2006) 2.63

Improving the fidelity of Thermus thermophilus DNA ligase. Nucleic Acids Res (1996) 2.58

Coming of age: ten years of next-generation sequencing technologies. Nat Rev Genet (2016) 2.48

A multiple-tubes approach for accurate genotyping of very small DNA samples by using PCR: statistical considerations. Am J Hum Genet (1992) 2.42

High-throughput genotyping of single nucleotide polymorphisms with rolling circle amplification. BMC Genomics (2001) 2.25

Single nucleotide primer extension to detect genetic diseases: experimental application to hemophilia B (factor IX) and cystic fibrosis genes. Proc Natl Acad Sci U S A (1991) 2.21

Single base pair mutation analysis by PNA directed PCR clamping. Nucleic Acids Res (1993) 2.20

Novel, ligation-dependent PCR assay for detection of hepatitis C in serum. J Clin Microbiol (1996) 2.19

Detection of single DNA base differences by competitive oligonucleotide priming. Nucleic Acids Res (1989) 2.14

Relevance of nucleic acid amplification techniques for diagnosis of respiratory tract infections in the clinical laboratory. Clin Microbiol Rev (1997) 2.11

A microsphere-based assay for multiplexed single nucleotide polymorphism analysis using single base chain extension. Genome Res (2000) 2.00

Single-well genotyping of diallelic sequence variations by a two-color ELISA-based oligonucleotide ligation assay. Nucleic Acids Res (1996) 1.93

Oligonucleotide ligation assay for detecting mutations in the human immunodeficiency virus type 1 pol gene that are associated with resistance to zidovudine, didanosine, and lamivudine. J Clin Microbiol (1998) 1.92

Advances in nucleic acid-based detection methods. Clin Microbiol Rev (1992) 1.84

Signature-based small molecule screening identifies cytosine arabinoside as an EWS/FLI modulator in Ewing sarcoma. PLoS Med (2007) 1.82

Fine-mapping of quantitative trait loci by identity by descent in outbred populations: application to milk production in dairy cattle. Proc Natl Acad Sci U S A (1999) 1.67

Rapid and sensitive oligonucleotide ligation assay for detection of mutations in human immunodeficiency virus type 1 associated with high-level resistance to protease inhibitors. J Clin Microbiol (2002) 1.66

Enhanced DNA sequencing by hybridization. Proc Natl Acad Sci U S A (1994) 1.61

Merosin-deficient congenital muscular dystrophy. Partial genetic correction in two mouse models. J Clin Invest (1998) 1.60

Specific, sensitive, and rapid assay for human immunodeficiency virus type 1 pol mutations associated with resistance to zidovudine and didanosine. J Clin Microbiol (1995) 1.57

RNA-templated DNA ligation for transcript analysis. Nucleic Acids Res (2001) 1.54

The effect of polymorphisms in the enhancer of split gene complex on bristle number variation in a large wild-caught cohort of Drosophila melanogaster. Genetics (2005) 1.52

Assessing long-distance RNA sequence connectivity via RNA-templated DNA-DNA ligation. Elife (2015) 1.50

PCR-generated padlock probes detect single nucleotide variation in genomic DNA. Nucleic Acids Res (2000) 1.46

Minority variants of drug-resistant HIV. J Infect Dis (2010) 1.44

Optimization of the oligonucleotide ligation assay, a rapid and inexpensive test for detection of HIV-1 drug resistance mutations, for non-North American variants. J Acquir Immune Defic Syndr (2008) 1.43

Detection of point mutations with a modified ligase chain reaction (Gap-LCR). Nucleic Acids Res (1995) 1.42

High-density multiplex detection of nucleic acid sequences: oligonucleotide ligation assay and sequence-coded separation. Nucleic Acids Res (1994) 1.41

The observed human sperm mutation frequency cannot explain the achondroplasia paternal age effect. Proc Natl Acad Sci U S A (2002) 1.39

Single nucleotide polymorphism seeking long term association with complex disease. Nucleic Acids Res (2002) 1.33

Prevalence of CYP2B6 alleles in malaria-endemic populations of West Africa and Papua New Guinea. Eur J Clin Pharmacol (2006) 1.30

A third base pair for the polymerase chain reaction: inserting isoC and isoG. Nucleic Acids Res (2004) 1.30

Association genetics of coastal Douglas fir (Pseudotsuga menziesii var. menziesii, Pinaceae). I. Cold-hardiness related traits. Genetics (2009) 1.27

SNP identification in unamplified human genomic DNA with gold nanoparticle probes. Nucleic Acids Res (2005) 1.22

A colorimetric method for point mutation detection using high-fidelity DNA ligase. Nucleic Acids Res (2005) 1.21

Discrimination of Listeria monocytogenes from other Listeria species by ligase chain reaction. Appl Environ Microbiol (1992) 1.21

Rapid preimplantation detection of mutant (shiverer) and normal alleles of the mouse myelin basic protein gene allowing selective implantation and birth of live young. Proc Natl Acad Sci U S A (1990) 1.19

Sequencing by Cyclic Ligation and Cleavage (CycLiC) directly on a microarray captured template. Nucleic Acids Res (2008) 1.16

Mutation detection using nucleotide analogs that alter electrophoretic mobility. Nucleic Acids Res (1989) 1.16

RASL-seq for massively parallel and quantitative analysis of gene expression. Curr Protoc Mol Biol (2012) 1.16

Genetic alterations and epithelial dysplasia in juvenile polyposis syndrome and sporadic juvenile polyps. Am J Pathol (1997) 1.15

Extremely sensitive, background-free gene detection using binary probes and beta replicase. Proc Natl Acad Sci U S A (1996) 1.15

Detection of hepatitis C virus RNA using ligation-dependent polymerase chain reaction in formalin-fixed, paraffin-embedded liver tissues. Am J Pathol (1996) 1.12

Effects of base mismatches on joining of short oligodeoxynucleotides by DNA ligases. Nucleic Acids Res (1997) 1.12

CCR: a rapid and simple approach for mutation detection. Nucleic Acids Res (1997) 1.11

SNPWave: a flexible multiplexed SNP genotyping technology. Nucleic Acids Res (2004) 1.10

Rapid detection of point mutations conferring resistance to fluoroquinolone in gyrA of Helicobacter pylori by allele-specific PCR. J Clin Microbiol (2006) 1.10

No evidence for an association between common nonsynonymous polymorphisms in delta and bristle number variation in natural and laboratory populations of Drosophila melanogaster. Genetics (2004) 1.10

Competitive enzymatic reaction to control allele-specific extensions. Nucleic Acids Res (2005) 1.09

L-RCA (ligation-rolling circle amplification): a general method for genotyping of single nucleotide polymorphisms (SNPs). Nucleic Acids Res (2001) 1.08

PathogenMip assay: a multiplex pathogen detection assay. PLoS One (2007) 1.06

Photocleavable biotin phosphoramidite for 5'-end-labeling, affinity purification and phosphorylation of synthetic oligonucleotides. Nucleic Acids Res (1996) 1.06

Detection of single base changes in nucleic acids. Biochem J (1989) 1.05

Improvements to bead-based oligonucleotide ligation SNP genotyping assays. Biotechniques (2008) 1.04

Fluorescence detection of single-nucleotide polymorphisms with a single, self-complementary, triple-stem DNA probe. Angew Chem Int Ed Engl (2009) 1.04

Unexpected substrate specificity of T4 DNA ligase revealed by in vitro selection. Nucleic Acids Res (1993) 1.04

Competitive amplification and unspecific amplification in polymerase chain reaction with confronting two-pair primers. J Mol Diagn (2002) 1.03

Homogeneous point mutation detection by quantum dot-mediated two-color fluorescence coincidence analysis. Nucleic Acids Res (2006) 1.03

Lock and roll: single-molecule genotyping in situ using padlock probes and rolling-circle amplification. Histochem Cell Biol (2006) 1.03

SNP typing by apyrase-mediated allele-specific primer extension on DNA microarrays. Nucleic Acids Res (2002) 1.02

RNA-Seq technology and its application in fish transcriptomics. OMICS (2013) 1.02

A low-cost open-source SNP genotyping platform for association mapping applications. Genome Biol (2005) 1.00

Mutational spectrometry without phenotypic selection: human mitochondrial DNA. Nucleic Acids Res (1997) 1.00

Labeling DNA for single-molecule experiments: methods of labeling internal specific sequences on double-stranded DNA. Nanoscale (2011) 1.00

Identification and physical mapping of a polymorphic human T cell receptor V beta gene with a frequent null allele. J Exp Med (1993) 1.00

Universal ligation-detection-reaction microarray applied for compost microbes. BMC Microbiol (2008) 0.99

Detection of Chlamydia trachomatis by isothermal ramification amplification method: a feasibility study. J Clin Microbiol (2002) 0.98

Testing the feasibility of DNA typing for human identification by PCR and an oligonucleotide ligation assay. Am J Hum Genet (1996) 0.97

Temperature switch PCR (TSP): Robust assay design for reliable amplification and genotyping of SNPs. BMC Genomics (2009) 0.96

Conditionally fluorescent molecular probes for detecting single base changes in double-stranded DNA. Nat Chem (2013) 0.95

Profiling the selectivity of DNA ligases in an array format with mass spectrometry. Nucleic Acids Res (2009) 0.95

Analysis of single nucleotide polymorphisms with solid phase invasive cleavage reactions. Nucleic Acids Res (2001) 0.95

DNA polymerases drive DNA sequencing-by-synthesis technologies: both past and present. Front Microbiol (2014) 0.95

A ligation assay for multiplex analysis of CpG methylation using bisulfite-treated DNA. Nucleic Acids Res (2007) 0.93

Prevalence and impact of minority variant drug resistance mutations in primary HIV-1 infection. PLoS One (2011) 0.93

Canonical nucleosides can be utilized by T4 DNA ligase as universal template bases at ligation junctions. Nucleic Acids Res (2003) 0.93

Rapid identification of bio-molecules applied for detection of biosecurity agents using rolling circle amplification. PLoS One (2012) 0.91

Rapid oligonucleotide-templated fluorogenic tetrazine ligations. Nucleic Acids Res (2013) 0.90

Molecular techniques for pathogen identification and fungus detection in the environment. IMA Fungus (2011) 0.90

Combinatorial library diversity: probability assessment of library populations. Nucleic Acids Res (1998) 0.90

RNase H-dependent PCR (rhPCR): improved specificity and single nucleotide polymorphism detection using blocked cleavable primers. BMC Biotechnol (2011) 0.90

Viral and microbial genotyping by a combination of multiplex competitive hybridization and specific extension followed by hybridization to generic tag arrays. Nucleic Acids Res (2003) 0.90

Development and evaluation of an oligonucleotide ligation assay for detection of drug resistance-associated mutations in the human immunodeficiency virus type 2 pol gene. J Clin Microbiol (2007) 0.89

Application of hybridization control probe to increase accuracy on ligation detection or minisequencing diagnostic microarrays. BMC Res Notes (2009) 0.89

In situ detection of Anaplasma spp. by DNA target-primed rolling-circle amplification of a padlock probe and intracellular colocalization with immunofluorescently labeled host cell von Willebrand factor. J Clin Microbiol (2008) 0.89

Single nucleotide polymorphism detection by combinatorial fluorescence energy transfer tags and biotinylated dideoxynucleotides. Nucleic Acids Res (2002) 0.89

An electrochemical sensor for single nucleotide polymorphism detection in serum based on a triple-stem DNA probe. J Am Chem Soc (2009) 0.89

Replication of a genome-wide case-control study of esophageal squamous cell carcinoma. Int J Cancer (2008) 0.88

Padlock and proximity probes for in situ and array-based analyses: tools for the post-genomic era. Comp Funct Genomics (2003) 0.88

Genetic analysis with random amplified polymorphic DNA markers. Plant Physiol (1993) 0.87

Real-time monitoring of nucleic acid ligation in homogenous solutions using molecular beacons. Nucleic Acids Res (2003) 0.87

Copy number variation and differential expression of a protective endogenous retrovirus in sheep. PLoS One (2012) 0.87

Articles by these authors

Initial sequencing and analysis of the human genome. Nature (2001) 212.86

A common language for physical mapping of the human genome. Science (1989) 17.36

Integrated genomic and proteomic analyses of a systematically perturbed metabolic network. Science (2001) 17.11

A physical map of the human genome. Nature (2001) 12.39

An immunoglobulin heavy chain variable region gene is generated from three segments of DNA: VH, D and JH. Cell (1980) 10.35

Two mRNAs can be produced from a single immunoglobulin mu gene by alternative RNA processing pathways. Cell (1980) 9.86

DNA diagnostics--molecular techniques and automation. Science (1988) 8.85

Gene families: the taxonomy of protein paralogs and chimeras. Science (1997) 8.80

A new approach to decoding life: systems biology. Annu Rev Genomics Hum Genet (2001) 7.79

Public-health impact of outdoor and traffic-related air pollution: a European assessment. Lancet (2000) 6.95

Alagille syndrome is caused by mutations in human Jagged1, which encodes a ligand for Notch1. Nat Genet (1997) 6.66

Two mRNAs with different 3' ends encode membrane-bound and secreted forms of immunoglobulin mu chain. Cell (1980) 6.32

A single VH gene segment encodes the immune response to phosphorylcholine: somatic mutation is correlated with the class of the antibody. Cell (1981) 5.87

Genome sequence of Halobacterium species NRC-1. Proc Natl Acad Sci U S A (2000) 5.87

The organization, expression, and evolution of antibody genes and other multigene families. Annu Rev Genet (1975) 5.87

A pseudogene homologous to mouse transplantation antigens: transplantation antigens are encoded by eight exons that correlate with protein domains. Cell (1981) 5.43

Underuse of coronary revascularization procedures in patients considered appropriate candidates for revascularization. N Engl J Med (2001) 5.29

A molecular map of the immune response region from the major histocompatibility complex of the mouse. Nature (1982) 5.12

Three cDNA clones encoding mouse transplantation antigens: homology to immunoglobulin genes. Cell (1981) 4.95

Pairwise end sequencing: a unified approach to genomic mapping and sequencing. Genomics (1995) 4.83

Clusters of genes encoding mouse transplantation antigens. Cell (1982) 4.71

Antibody diversity: somatic hypermutation of rearranged VH genes. Cell (1981) 4.65

A new strategy for genome sequencing. Nature (1996) 4.61

Transgenic mice that express a myelin basic protein-specific T cell receptor develop spontaneous autoimmunity. Cell (1993) 4.59

Concordance of the toxicity of pharmaceuticals in humans and in animals. Regul Toxicol Pharmacol (2000) 4.58

Restricted use of T cell receptor V genes in murine autoimmune encephalomyelitis raises possibilities for antibody therapy. Cell (1988) 4.47

Genes of the major histocompatibility complex of the mouse. Annu Rev Immunol (1983) 4.44

A comparison of allogeneic bone marrow transplantation, autologous bone marrow transplantation, and aggressive chemotherapy in children with acute myeloid leukemia in remission. Blood (2001) 4.19

An immunoglobulin heavy-chain gene is formed by at least two recombinational events. Nature (1980) 3.99

Striking sequence similarity over almost 100 kilobases of human and mouse T-cell receptor DNA. Nat Genet (1994) 3.88

IgG antibodies to phosphorylcholine exhibit more diversity than their IgM counterparts. Nature (1981) 3.86

Prostate-localized and androgen-regulated expression of the membrane-bound serine protease TMPRSS2. Cancer Res (1999) 3.79

Silkmoth chorion proteins: sequence analysis of the products of a multigene family. Proc Natl Acad Sci U S A (1978) 3.60

Structural studies of the scrapie prion protein using mass spectrometry and amino acid sequencing. Biochemistry (1993) 3.54

Introduced T cell receptor variable region gene segments recombine in pre-B cells: evidence that B and T cells use a common recombinase. Cell (1986) 3.51

Large-scale and automated DNA sequence determination. Science (1991) 3.45

Cell-type-specific cDNA probes and the murine I region: the localization and orientation of Ad alpha. Proc Natl Acad Sci U S A (1984) 3.43

The human T cell antigen receptor is encoded by variable, diversity, and joining gene segments that rearrange to generate a complete V gene. Cell (1984) 3.41

Death receptor 5, a new member of the TNFR family, and DR4 induce FADD-dependent apoptosis and activate the NF-kappaB pathway. Immunity (1997) 3.33

T cell antigen receptors and the immunoglobulin supergene family. Cell (1985) 3.23

Cell-cell interaction in prostate gene regulation and cytodifferentiation. Proc Natl Acad Sci U S A (1997) 3.22

Immunoglobulin heavy chain gene organization in mice: analysis of a myeloma genomic clone containing variable and alpha constant regions. Proc Natl Acad Sci U S A (1979) 3.19

The structure, rearrangement and expression of D beta gene segments of the murine T-cell antigen receptor. Nature (1984) 3.18

DNA sequence of a gene encoding a BALB/c mouse Ld transplantation antigen. Science (1982) 3.17

Mechanism of antibody diversity: germ line basis for variability. Science (1970) 3.05

Predominant use of a V alpha gene segment in mouse T-cell receptors for cytochrome c. Nature (1987) 2.99

Understanding the adaptation of Halobacterium species NRC-1 to its extreme environment through computational analysis of its genome sequence. Genome Res (2001) 2.92

Complete genomic sequence and analysis of 117 kb of human DNA containing the gene BRCA1. Genome Res (1996) 2.91

Regular physical exercise corrects endothelial dysfunction and improves exercise capacity in patients with chronic heart failure. Circulation (1998) 2.90

Automated DNA diagnostics using an ELISA-based oligonucleotide ligation assay. Proc Natl Acad Sci U S A (1990) 2.88

Genes of the major histocompatibility complex in mouse and man. Science (1983) 2.88

Rearrangement of genetic information may produce immunoglobulin diversity. Nature (1979) 2.84

Mechanism of antibody synthesis: size differences between mouse kappa chains. Science (1967) 2.77

Zinc-dependent structure of a single-finger domain of yeast ADR1. Science (1988) 2.76

DNA sequence determination by hybridization: a strategy for efficient large-scale sequencing. Science (1993) 2.76

From hematopoiesis to neuropoiesis: evidence of overlapping genetic programs. Proc Natl Acad Sci U S A (2001) 2.66

Dynorphin-(1-13), an extraordinarily potent opioid peptide. Proc Natl Acad Sci U S A (1979) 2.66

The complete 685-kilobase DNA sequence of the human beta T cell receptor locus. Science (1996) 2.62

Mouse Cmu heavy chain immunoglobulin gene segment contains three intervening sequences separating domains. Nature (1980) 2.52

Separate elements control DJ and VDJ rearrangement in a transgenic recombination substrate. EMBO J (1990) 2.52

Identification of the class I genes of the mouse major histocompatibility complex by DNA-mediated gene transfer. Nature (1982) 2.48

European guidelines on the clinical management of HIV-1 tropism testing. Lancet Infect Dis (2011) 2.47

Comparative hybridization of an array of 21,500 ovarian cDNAs for the discovery of genes overexpressed in ovarian carcinomas. Gene (1999) 2.45

Messenger RNA translation state: the second dimension of high-throughput expression screening. Proc Natl Acad Sci U S A (1999) 2.42

Secondary cancers after bone marrow transplantation for leukemia or aplastic anemia. N Engl J Med (1989) 2.42

Mouse c-myc oncogene is located on chromosome 15 and translocated to chromosome 12 in plasmacytomas. Science (1982) 2.40

Genomic organization of the genes encoding mouse T-cell receptor alpha-chain. Nature (1985) 2.40

Cloning and characterization of two Toll/Interleukin-1 receptor-like genes TIL3 and TIL4: evidence for a multi-gene receptor family in humans. Blood (1998) 2.33

Direct evidence for chromosomal inversion during T-cell receptor beta-gene rearrangements. Nature (1986) 2.33

Rearrangement and transcription of the beta-chain genes of the T-cell antigen receptor in different types of murine lymphocytes. Nature (1985) 2.29

Expression of a myelin basic protein gene in transgenic shiverer mice: correction of the dysmyelinating phenotype. Cell (1987) 2.29

The joining of V and J gene segments creates antibody diversity. Nature (1980) 2.28

Lyme borreliosis: clinical case definitions for diagnosis and management in Europe. Clin Microbiol Infect (2011) 2.23

The human homolog of rat Jagged1 expressed by marrow stroma inhibits differentiation of 32D cells through interaction with Notch1. Immunity (1998) 2.23

Modulation of the NF-kappa B pathway by virally encoded death effector domains-containing proteins. Oncogene (1999) 2.21

Diversity and structure of human T-cell receptor beta-chain variable region genes. Proc Natl Acad Sci U S A (1986) 2.19

Outcome of unrelated donor bone marrow transplantation in 40 children with Hurler syndrome. Blood (1996) 2.19

Assessment of deaths attributable to air pollution: should we use risk estimates based on time series or on cohort studies? Am J Epidemiol (2001) 2.19

Rearranged beta T cell receptor genes in a helper T cell clone specific for lysozyme: no correlation between V beta and MHC restriction. Cell (1985) 2.14

Systems cancer medicine: towards realization of predictive, preventive, personalized and participatory (P4) medicine. J Intern Med (2012) 2.13

Nucleotide sequence of a light chain gene of the mouse I-A subregion: A beta d. Science (1983) 2.12

Gene transfer of H-2 class II genes: antigen presentation by mouse fibroblast and hamster B-cell lines. Cell (1984) 2.12

Timed-sequential induction therapy improves postremission outcome in acute myeloid leukemia: a report from the Children's Cancer Group. Blood (1996) 2.12

Evidence for a rare prostate cancer-susceptibility locus at chromosome 1p36. Am J Hum Genet (1999) 2.12

Modeling the feasibility of whole genome shotgun sequencing using a pairwise end strategy. Genomics (2000) 2.05

Preclinical evaluation of HBY 097, a new nonnucleoside reverse transcriptase inhibitor of human immunodeficiency virus type 1 replication. Antimicrob Agents Chemother (1995) 2.04

Chromosomal mapping of mouse myelin basic protein gene and structure and transcription of the partially deleted gene in shiverer mutant mice. Cell (1985) 2.02

Pulsed field gel electrophoresis. Biotechniques (1989) 2.02

Soluble protein of the organic matrix of mollusk shells: a potential template for shell formation. Science (1975) 1.99

Development and clinical significance of the musculus dorsoepitrochlearis in men. Clin Anat (2009) 1.98

Cloning and characterization of the myelin basic protein gene from mouse: one gene can encode both 14 kd and 18.5 kd MBPs by alternate use of exons. Cell (1985) 1.98

Asparagine-linked glycosylation of the scrapie and cellular prion proteins. Arch Biochem Biophys (1989) 1.96

Expression of a murine polyclonal T cell receptor marker correlates with the use of specific members of the V beta 8 gene segment subfamily. J Exp Med (1987) 1.96

Genetic mapping in the major histocompatibility complex by restriction enzyme site polymorphisms: most mouse class I genes map to the Tla complex. Proc Natl Acad Sci U S A (1983) 1.96

Interleukin-6 gene -174g>c and -572g>c promoter polymorphisms are strong predictors of plasma interleukin-6 levels after coronary artery bypass surgery. Arterioscler Thromb Vasc Biol (2001) 1.96

Immunoglobulin structure: amino terminal sequences of mouse myeloma proteins that bind phosphorylcholine. Science (1974) 1.94

Amino acid sequence of homogeneous antibodies to dextran and DNA rearrangements in heavy chain V-region gene segments. Nature (1980) 1.94