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PubMed2003

Internet Contig Explorer (iCE)--a tool for visualizing clone fingerprint maps.

Fingerprinted clone physical maps have proven useful in various applications, supporting both whole-genome and region-specific DNA sequencing as well as gene cloning studies. Fingerprint maps have been generated for several genomes, including those of human, mouse, rat, the nematodes Caenorhabditis elegans and Caenorhabditis briggsae, Arabidopsis thaliana and rice. Fingerprint maps of other genomes, including those of fungi, bacteria, poplar, and the cow, are being generated. The increasing use of fingerprint maps in genomic research has spawned a need in the research community for intuitive computer tools that facilitate viewing of the maps and the underlying fingerprint data. In this report we describe a new Java-based application called iCE (Internet Contig Explorer) that has been designed to provide views of fingerprint maps and associated data. Users can search for and display individual clones, contigs, clone fingerprints, clone insert sizes and markers. Users can also load into the software lists of particular clones of interest and view their fingerprints. iCE is being used at our Genome Centre to offer up to the research community views of the mouse, rat, bovine, C. briggsae, and several fungal genome bacterial artificial chromosome (BAC) fingerprint maps we have either completed or are currently constructing. We are also using iCE as part of the Rat Genome Sequencing Project to manage our provision of rat BAC clones for sequencing at the Human Genome Sequencing Center at the Baylor College of Medicine.

Animals↗
PubMed2000

The ins and outs of DNA fingerprinting the infectious fungi.

DNA fingerprinting methods have evolved as major tools in fungal epidemiology. However, no single method has emerged as the method of choice, and some methods perform better than others at different levels of resolution. In this review, requirements for an effective DNA fingerprinting method are proposed and procedures are described for testing the efficacy of a method. In light of the proposed requirements, the most common methods now being used to DNA fingerprint the infectious fungi are described and assessed. These methods include restriction fragment length polymorphisms (RFLP), RFLP with hybridization probes, randomly amplified polymorphic DNA and other PCR-based methods, electrophoretic karyotyping, and sequencing-based methods. Procedures for computing similarity coefficients, generating phylogenetic trees, and testing the stability of clusters are then described. To facilitate the analysis of DNA fingerprinting data, computer-assisted methods are described. Finally, the problems inherent in the collection of test and control isolates are considered, and DNA fingerprinting studies of strain maintenance during persistent or recurrent infections, microevolution in infecting strains, and the origin of nosocomial infections are assessed in light of the preceding discussion of the ins and outs of DNA fingerprinting. The intent of this review is to generate an awareness of the need to verify the efficacy of each DNA fingerprinting method for the level of genetic relatedness necessary to answer the epidemiological question posed, to use quantitative methods to analyze DNA fingerprint data, to use computer-assisted DNA fingerprint analysis systems to analyze data, and to file data in a form that can be used in the future for retrospective and comparative studies.

DNA Fingerprinting↗
PubMed1998

Diversity of DNA fingerprints of Mycobacterium tuberculosis isolates in the United States.

To investigate the diversity of IS6110 fingerprints of Mycobacterium tuberculosis isolates in the United States and to determine if matching IS6110 fingerprints represent recent interstate tuberculosis transmission, we performed restriction fragment length polymorphism analysis of M. tuberculosis isolates from 1,326 patients in three geographically separated states. Seven hundred ninety-five different IS6110 fingerprint patterns were generated, and pattern diversity was similar in each state. Ninety-six percent of the fingerprint patterns were observed in only one state, demonstrating that most IS6110 fingerprint patterns are confined to a single geographic location. Of the IS6110 fingerprint patterns that were shared by isolates from more than one state, most isolates with 1 to 5 IS6110 copies were separable by pTBN12 fingerprinting whereas those with > 15 copies were not. One high-copy-number M. tuberculosis strain had identical IS6110 and pTBN12 fingerprints and included 57 isolates from three states. Epidemiological data demonstrated significant recent transmission of tuberculosis within each city but not among the states. This suggests that identical fingerprints of isolates from geographically separate locations most likely reflect interstate tuberculosis transmission in the past, with subsequent intrastate spread of disease. Further evaluation of M. tuberculosis strains that cause outbreaks in different geographic locations will provide insight into the epidemiological and bacteriological factors that facilitate the spread of tuberculosis.

DNA Fingerprinting↗
PubMed1999

Abnormal patterns of immunoglobulin heavy chain gene DNA fingerprinting during chronic phase chronic myeloid leukemia.

Using IgH DNA fingerprinting we have previously demonstrated clonal immunoglobulin heavy chain (IgH) gene rearrangements during chronic phase (CP) chronic myeloid leukemia (CML) in patients destined to develop lymphoid blast crisis (L-BC). In view of this we decided to follow a cohort of CP CML patients to determine the frequency with which abnormal IgH fingerprints are found and their relationship, if any, to treatment regimen. Thirty three, initially CP, CML patients were studied on 111 occasions over a 16 month period using consensus PCR amplification of the third complementarity determining region (CDR3) of the IgH gene and high resolution polyacrylamide gel electrophoresis (IgH DNA fingerprinting). Of these 33 patients, thirteen received interferon-alpha (IFN) containing regimens and 15 non-IFN containing regimens throughout the study period. Five patients received variable therapy. During the period of observation 7 patients experienced disease progression: 5 accelerated phase, I L-BC and I myeloid blast crisis (M-BC). Abnormal IgH fingerprints were seen in 29 of the 111 (26%) specimens analysed. The 28 patients who received uniform therapy (IFN or non-IFN) over the 16 months were classified as "normal" (n = 18, normal pattern on all occasions) or "abnormal" (n = 10, abnormal on 1 or more occasions). Analysis by patient group (normal vs abnormal) showed that fingerprint abnormalities were associated with an elevated peripheral blood lymphocyte count (p = 0.0001) but not with changes in the total white cell count. Comparison of the IFN vs. non-IFN groups showed the former all had normal patterns whereas 10 of 15 non-IFN therapy patients were abnormal (p = 0.00023). The peripheral blood lymphocyte counts in the normal vs abnormal patients within the non-IFN group were not significantly different. The patient who developed L-BC demonstrated a persistent IgH fingerprint pattern abnormality from 7 months prior to the diagnosis of L-BC. The M-BC patient had a normal pattern at all times. We conclude that: (1) abnormal IgH fingerprints are found in a significant number of CP CML patients; (2) in this cohort the use of IFN was associated with normal CP CML IgH fingerprints, and (3) detection of abnormal IgH fingerprints may be highly predictive for the lineage of impending blast crisis.

DNA Fingerprinting↗
PubMed2005

An approach to develop two-dimensional fingerprint for the quality control of Qingkailing injection by high-performance liquid chromatography with diode array detection.

An approach was proposed to develop two-dimensional fingerprint (2D fingerprint) by means of principal component analysis (PCA) of high-performance liquid chromatography with diode array detection (HPLC/DAD) data. The approach was applied to establish 2D fingerprints of various Qingkailing injections which were produced by different manufacturers and procedures. In comparison with common one-dimensional fingerprint (ID fingerprint) at fixed wavelength, 2D fingerprint compiled additional spectral data and was hence more informative. Principal component analysis of the 2D fingerprint data was performed in this study, and it led to an accurate classification of various samples on their manufacturers and procedures. The quality of Qingkailing samples was further evaluated by similarity measures and the same results were achieved. For comparison, four conventional ID fingerprints were also applied to the quality assessment for the same samples. Finally, we demonstrated that 2D fingerprint was a more powerful tool to characterize the quality of samples, and could be used to comprehensively conduct the quality control of traditional Chinese medicines.

Chromatography, High Pressure Liquid↗
PubMed2004

Potential usefulness of biological fingerprints in chest radiographs for automated patient recognition and identification.

RATIONALE AND OBJECTIVES: The purpose of this study was to demonstrate the potential usefulness of "biological fingerprints" in chest radiographs for automated patient recognition and identification. MATERIALS AND METHODS: Thoracic fields, cardiac shadows, the superior mediastinum, lung apices, a part of the right lung, and the right lower lung that includes the costophrenic angle were used as biological fingerprints in chest radiographs. Each of the biological fingerprints in a current chest radiograph was used as a template for determination of the correlation value with the corresponding biological fingerprint in a previous chest radiograph for patient recognition and identification. The overall performance of the method developed was examined in terms of receiver operating characteristic curves. RESULTS: Receiver operating characteristic curves obtained with different biological fingerprints, except for the part of the right lung, indicated a high performance in identifying patients. These results showed that a new concept of biological fingerprints in radiologic images would be useful in patient recognition and identification. The low performance with the part of the right lung seems to be related to a general observation that this region does not usually include features unique to a specific patient. The performance of the artificial neural networks by use of a combination of five biological fingerprints was higher than results obtained with each biological fingerprint. CONCLUSION: The use of automated patient identification based on biological fingerprints in chest radiographs is promising for helping to discover misfiled patient images, especially in a picture archiving and communication system environment.

Dermatoglyphics↗
PubMed2006

Fingerprint multicast in secure video streaming.

Digital fingerprinting is an emerging technology to protect multimedia content from illegal redistribution, where each distributed copy is labeled with unique identification information. In video streaming, huge amount of data have to be transmitted to a large number of users under stringent latency constraints, so the bandwidth-efficient distribution of uniquely fingerprinted copies is crucial. This paper investigates the secure multicast of anticollusion fingerprinted video in streaming applications and analyzes their performance. We first propose a general fingerprint multicast scheme that can be used with most spread spectrum embedding-based multimedia fingerprinting systems. To further improve the bandwidth efficiency, we explore the special structure of the fingerprint design and propose a joint fingerprint design and distribution scheme. From our simulations, the two proposed schemes can reduce the bandwidth requirement by 48% to 87%, depending on the number of users, the characteristics of video sequences, and the network and computation constraints. We also show that under the constraint that all colluders have the same probability of detection, the embedded fingerprints in the two schemes have approximately the same collusion resistance. Finally, we propose a fingerprint drift compensation scheme to improve the quality of the reconstructed sequences at the decoder's side without introducing extra communication overhead.

Algorithms↗
PubMed2006

Fingerprint registration by maximization of mutual information.

Fingerprint registration is a critical step in fingerprint matching. Although a variety of registration alignment algorithms have been proposed, accurate fingerprint registration remains an unresolved problem. We propose a new algorithm for fingerprint registration using orientation field. This algorithm finds the correct alignment by maximization of mutual information between features extracted from orientation fields of template and input fingerprint images. Orientation field, representing the flow of ridges, is a relatively stable global feature of fingerprint images. This method uses the statistics and distribution of global feature of fingerprint images so that it is robust to image quality and local changes in images. The primary characteristic of this method is that it uses this stable global feature to align fingerprints, and that its behavior may resemble the way humans compare fingerprints. Experimental results show that the occurrence of misalignment is dramatically reduced and that registration accuracy is greatly improved at the same time, leading to enhanced matching performance.

Algorithms↗
PubMed1997

The limits of random fingerprinting.

Various random fingerprinting methods are sometimes used to detect overlap between pairs of clones as a first step toward producing a minimal tiling path of clones for subsequent mapping and sequencing efforts. This paper evaluates and compares various statistical procedures for detecting pairwise overlap between clones when the fingerprints arise from any random process meeting simple, plausible assumptions about the relationship between overlap and the resulting fingerprint. Examples of such random processes include, but are not limited to, large-scale hybridization procedures designed to prepare tiling paths of clones for subsequent large-scale genomic sequencing. Our goals are to assess how well random fingerprinting can possibly detect overlap, to assess the effects of inevitable fingerprinting errors on statistical detection, to determine how one can make the best use of the data random fingerprinting provides, and to evaluate how well simple, heuristic techniques for overlap detection compare to more complex, likelihood-based approaches. The paper provides a quantitative assessment of the ability of any random fingerprinting procedure to detect various proportions of clonal overlap and shows the extent to which a small amount of experimental error will vitiate the performance of such techniques. The paper outlines a simple approximation method for constructing Bayesian overlap detectors, while concluding that detectors constructed from linear combinations of fingerprint data can be designed that will perform nearly as well as more complex, likelihood-based approaches.

DNA Fingerprinting↗
PubMed2002

Archived or directly swabbed latent fingerprints as a DNA source for STR typing.

Former studies [Nature (1997) 387, Electrophoresis 20 (1999) 2870, P. Van Renterghem, D. Leonard, C. De Greef, Progress in Forensic Genetics, Vol. 8, 2000, p. 501, J. Forensic Sci. 45 (3) (2000) 687] have shown that even a single skin contact, documented by a latent fingerprint, can transfer enough DNA for a genetic analysis. It was proven in these studies that it is possible to swab fingerprints from surfaces [Nature (1997) 387, Electrophoresis 20 (1999) 2870, P. Van Renterghem, D. Leonard, C. De Greef, Progress in Forensic Genetics, Vol. 8, 2000, p. 501] and use them as a DNA source. Usually, however, discovered fingerprints are removed with scotch tape and placed on evidence cards for further investigation.In this study, we tried to assess the potential use of latent fingerprints as a DNA source for STR typing. The materials (magnetic powder, soot powder and scotch tape) used for visualization and archiving fingerprints in Germany were tested for their PCR inhibitory characteristics. Then, fingerprints were placed on clean glass surfaces, visualized and tested for their usefulness as a DNA source. Obtained DNA was quantified and tested in an STR system. Partly it proved possible to type fingerprints taken directly from the surface as well as fingerprints removed from the surface with scotch tape.

DNA Fingerprinting↗
PubMed2003

Telomere fingerprinting for assessing chromosome number, isolate typing and recombination in the entomopathogen Beauveria bassiana.

Beauveria bassiana is a popular biocontrol agent used as 'green' pesticide in crop insect pest management. Chromosome number has been variously reported as five, six, seven and eight in this species. The range of chromosome number and the minimum chromosome number in this economically important fungus were assessed through telomere fingerprint analysis of a sample of 17 isolates from different and similar hosts and distant and same geographic origin. Genomic DNA digested with EcoRI, which has no cutting site in the telomere repeat sequence arrays was probed with a radioisotope-labelled (5'-TTAGGG-3')s oligonucleotide. The probe-hybridised regions appeared as discrete bands--each representing a telomere. The number of bands in each lane was counted and halved to arrive at the chromosome number of that isolate. The chromosome number varied from 5 to 10 in the different isolates. The telomere probe hybridised bands were also scored for presence or absence in a 0-1 matrix and a dendrogram based on similarities between the isolates was constructed using the NTSYS-pc ver. 2.02i software. The isolates showed very little similarity; the overall similarity was 14%. Only two isolates which were of diverse host and geographic origin showed 100% similarity. Isolates from the same epizootic that showed 43% similarity in their telomere fingerprints had 96 % similarity in their RAPD (Random amplified polymorphic DNA) fingerprints with 10 primers. The genetic distances computed from any one DNA fingerprinting method thus do not reflect the true genetic similarities of the isolates. The frequency distribution pattern of the pair-wise similarities computed from telomere fingerprints hinted at the occurrence of recombination in this fungus. Telomere fingerprinting proved very useful in typing isolates since each of them was found to have a unique fingerprint. Isolates with the same chromosome number neither showed a distinct morphology or virulence character nor a close similarity in telomere or RAPD fingerprints to merit their subgrouping into a taxonomically relevant or practically useful unit.

Animals↗
PubMedDate not supplied

Fingerprint scaling increases the probability of identifying molecules with similar activity in virtual screening calculations.

Results of systematic virtual screening calculations using a structural key-type fingerprint are reported for compounds belonging to 14 activity classes added to randomly selected synthetic molecules. For each class, a fingerprint profile was calculated to monitor the relative occupancy of fingerprint bit positions. Consensus bit patterns were determined consisting of all bits that were always set on in compounds belonging to a specific activity class. In virtual screening calculations, scale factors were applied to each consensus bit position in fingerprints of query molecules. This technique, called "fingerprint scaling", effectively increases the weight of consensus bit positions in fingerprint comparisons. Although overall prediction accuracy was satisfactory using unscaled calculations, scaling significantly increased the number of correct predictions but only slightly increased the rate of false positives. These observations suggest that fingerprint scaling is an attractive approach to increase the probability of identifying molecules with similar activity by virtual screening. It requires the availability of a series of related compounds and can be easily applied to any keyed fingerprint representation that associates bit positions with specific molecular features.

Algorithms↗
PubMedDate not supplied

Anatomy of fingerprint search calculations on structurally diverse sets of active compounds.

Similarity searching using molecular fingerprints is a widely used approach for the identification of novel hits. A fingerprint search involves many pairwise comparisons of bit string representations of known active molecules with those precomputed for database compounds. Bit string overlap, as evaluated by various similarity metrics, is used as a measure of molecular similarity. Results of a number of studies focusing on fingerprints suggest that it is difficult, if not impossible, to develop generally applicable search parameters and strategies, irrespective of the compound classes under investigation. Rather, more or less, each individual search problem requires an adjustment of calculation conditions. Thus, there is a need for diagnostic tools to analyze fingerprint-based similarity searching. We report an analysis of fingerprint search calculations on different sets of structurally diverse active compounds. Calculations on five biological activity classes were carried out with two fingerprints in two compound source databases, and the results were analyzed in histograms. Tanimoto coefficient (Tc) value ranges where active compounds were detected were compared to the distribution of Tc values in the database. The analysis revealed that compound class-specific effects strongly influenced the outcome of these fingerprint calculations. Among the five diverse compound sets studied, very different search results were obtained. The analysis described here can be applied to determine Tc intervals where scaffold hopping occurs. It can also be used to benchmark fingerprint calculations or estimate their probability of success.

Chemical Phenomena↗
PubMed1997

Evaluation of the resolving power of three different DNA fingerprinting methods to discriminate among isolates of a natural Rhizobium meliloti population.

In a comparative study, the PCR-based RAPD and ERIC fingerprint methods were evaluated for their resolving power to discriminate among 21 isolates of a natural Rhizobium meliloti population. PCR fingerprint patterns were analysed by using an automated laser fluorescent (ALF) DNA sequencer, thus allowing the automated on-line storage of data. Results obtained were compared to a classification system using insertion sequence (IS) fingerprinting. Both PCR fingerprint methods were comparable in their ability to resolve differences amongst Rh. meliloti isolates. Grouping of strains on the basis of their RAPD as well as their ERIC fingerprints correlated with grouping of strains according to their IS fingerprints. Moreover, strains displaying identical PCR patterns could be further differentiated according to their IS fingerprints, thus allowing a detailed insight into phylogenetic relationship among strains. The automated evaluation of strain-specific fingerprint patterns has the potential to become a valuable tool for studies of bacterial population genetics. Moreover, the rapid identification of single strains, e.g. pathogens in epidemiological studies seems feasible.

Bacterial Typing Techniques↗
PubMed2006

Oligonucleotide fingerprint identification for microarray-based pathogen diagnostic assays.

MOTIVATION: Advances in DNA microarray technology and computational methods have unlocked new opportunities to identify 'DNA fingerprints', i.e. oligonucleotide sequences that uniquely identify a specific genome. We present an integrated approach for the computational identification of DNA fingerprints for design of microarray-based pathogen diagnostic assays. We provide a quantifiable definition of a DNA fingerprint stated both from a computational as well as an experimental point of view, and the analytical proof that all in silico fingerprints satisfying the stated definition are found using our approach. RESULTS: The presented computational approach is implemented in an integrated high-performance computing (HPC) software tool for oligonucleotide fingerprint identification termed TOFI. We employed TOFI to identify in silico DNA fingerprints for several bacteria and plasmid sequences, which were then experimentally evaluated as potential probes for microarray-based diagnostic assays. Results and analysis of approximately 150 in silico DNA fingerprints for Yersinia pestis and 250 fingerprints for Francisella tularensis are presented. AVAILABILITY: The implemented algorithm is available upon request.

Algorithms↗
PubMedDate not supplied

DNA amplification fingerprinting for subtyping Neisseria gonorrhoeae strains.

BACKGROUND AND OBJECTIVES: DNA amplification fingerprinting is used in most epidemiologic studies as a substitute for conventional typing methods. DNA amplification fingerprinting and conventional typing methods were compared in this epidemiologic study of Neisseria gonorrhoeae. GOAL OF THIS STUDY: To differentiate 70 Neisseria gonorrhoeae isolates from untreated patients with urogenital gonococcal infection. STUDY DESIGN: Gonococcal strains were characterized by auxotyping, serotyping, plasmid profile, antibiotic sensitivity, and DNA amplification fingerprinting. The method of unweighted pair-group average linkage was used for cluster analysis. Discriminatory power was calculated applying Simpson's index. RESULTS: Amplification of Neisseria gonorrhoeae DNA with primers OPA-03 and OPA-13 produced well-resolved patterns of 15 and 22 DNA fragments, respectively, with a discriminatory power (0.978 with OPA-13 and 0.967 with OPA-03) comparable to that obtained with auxotyping/serotyping combination (D:0.968) or with auxotype/serotype/plasmid profile combination (D:0.983). Correlation between DNA amplification fingerprinting pattern and auxotype/serotype class was not always uniform. Some strains with the same auxotype/serotype/plasmid profile were subdivided by DNA amplification fingerprinting, and vice versa. CONCLUSION: Although auxotype/serotype class and DNA amplification fingerprinting can be used in the epidemiologic characterization of strains, DNA amplification fingerprinting offers a better discriminatory index than the separate serotyping. It is especially useful for differentiating serologically identical strains and nontypable strains. A combination of serotyping and DNA amplification fingerprinting seems to be the best way to differentiate Neisseria gonorrhoeae strains in epidemiologic studies, bringing together the most simple techniques and the best discriminatory power among isolates.

Bacterial Typing Techniques↗
PubMed2000

Comparison of AFLP and rep-PCR genomic fingerprinting with DNA-DNA homology studies: Xanthomonas as a model system.

The genus Xanthomonas contains a large number of strains, which have been characterized by a variety of phenotypic and genotypic classification methods. The Xanthomonas collection constitutes one of the largest groups of bacteria that have been characterized phylogenetically by DNA-DNA homology studies and genomic fingerprinting. Presently, a total genomic DNA-DNA homology value of 70% represents an internationally accepted criterion to define bacterial species levels. However, the complexity of DNA-DNA reassociation kinetics methods precludes the rapid analysis of large numbers of bacterial isolates, which is imperative for molecular microbial diversity studies. Therefore, the aim of this study was to compare more facile PCR-based genomic fingerprinting techniques, such as repetitive-sequence-based (rep)-PCR and AFLP genomic fingerprinting, to DNA-DNA hybridization studies. Using three different primer sets, rep-PCR genomic fingerprint patterns were generated for 178 Xanthomonas strains, belonging to all 20 previously defined DNA-DNA homology groups, and one Stenotrophomonas maltophilia strain. In addition, AFLP genomic fingerprints were produced for a subset of 80 Xanthomonas strains belonging to the 20 DNA-DNA homology groups and for the S. maltophilia strain. Similarity values derived from rep-PCR- and AFLP-generated fingerprinting analyses were calculated and used to determine the correlation between rep-PCR- or AFLP-derived relationships and DNA-DNA homology values. A high correlation was observed, suggesting that genomic fingerprinting techniques truly reveal genotypic and phylogenetic relationships of organisms. On the basis of these studies, we propose that genomic fingerprinting techniques such as rep-PCR and AFLP can be used as rapid, highly discriminatory screening techniques to determine the taxonomic diversity and phylogenetic structure of bacterial populations.

Bacterial Typing Techniques↗
PubMed1991

The use of genomic DNA fingerprinting in studies of the epidemiology of bacteria in periodontitis.

Recent studies of microbial epidemiology emphasizing the genetic organization and distribution of organisms associated with orofacial infections have led to new insights into the possible origins of pathogenicity. Studies into genetic heterogeneity, acquisition and transmission of these organisms have been markedly advanced by the utilization of the powerful technique of genomic DNA fingerprinting. Characteristic fingerprints for each bacterial isolate can be produced by cleavage of high molecular weight genomic DNA by restriction endonucleases. It is assumed that each DNA fingerprint represents a clonal type. In this report, we review and analyze studies of the epidemiology of bacteria associated with orofacial infections with an emphasis on periodontal disease. Studies of nontypable (NT) Haemophilus influenzae associated with recurrent otitis media illustrate the utility of this technique. DNA fingerprinting clearly demonstrates genetic heterogeneity of NT H. influenzae isolates, and clonality of infection of any individual. Furthermore, DNA fingerprinting has shown that the same clonal type is seen in siblings concurrently suffering from otitis media, suggesting horizontal transmission within the family. Studies of mutans Streptococci also show extensive genetic heterogeneity and show vertical transmission of a predominant clonal type only from mother to infant, but not from father to infant. Studies of Actinobacillus actinomycetemcomitans show considerable genetic heterogeneity among monkey isolates. Thus far, three clonal types have been reported with DNA fingerprinting among isolates from periodontal patients, but additional genetic heterogeneity can be found using specific DNA fragments as probes in hybridization experiments. Intrafamilial transmission of A. actinomycetemcomitans has been demonstrated. Porphyromonas (Bacteroides) gingivalis shows extensive genetic heterogeneity and case reports suggest clonal infection of any one individual. In contrast, results with DNA fingerprinting of Eikenella corrodens, Fusobacterium nucleatum, and Bacteroides intermedius show that individuals may be infected with 2 or more clonal types. These studies point to the great potential of DNA fingerprinting for investigating the epidemiology of putative orofacial pathogens. Such studies with periodontal microorganisms will likely reveal steps in the acquisition, intraoral and person-to-person transmission, which then could possibly be inhibited or interfered with to prevent periodontal disease or its recurrence.

Bacteria↗