Chemistry: molecular biology and microbiology – Measuring or testing process involving enzymes or... – Involving nucleic acid
Reexamination Certificate
1999-10-29
2004-04-13
Jones, W. Gary (Department: 1634)
Chemistry: molecular biology and microbiology
Measuring or testing process involving enzymes or...
Involving nucleic acid
C435S091200, C536S024300, C536S023100, C204S450000
Reexamination Certificate
active
06720138
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to methods of preparing standard diagnostic gene transcript patterns, probe kits for diagnosis and methods of diagnosis using such kits.
BACKGROUND OF THE INVENTION
There are numerous examples of diagnostic methods that include physical, anatomical and behavioural examination and/or biochemical, electrical, or electromagnetic studies and/or assays.
SUMMARY OF THE INVENTION
These diagnostic methods are well developed and are often efficient means to identify many pathological conditions. They are based on recent developments and research as well as on the observations, experience and empirical data recorded by health-workers concerned with diseases of human beings, other animals and plants for at least 6000 years.
Never before has the arsenal of diagnostic tools been greater than at present, but even so, incorrect diagnosis of ailments and other conditions is still commonplace.
New diseases and conditions are found that may be related to environmental changes or mutations or other alterations in both the active agents or organisms as well as in the organism that is exposed. In addition a number of old and new illegal substances used in sports and by drug addicts do not have appropriate diagnostic tests for their presence.
Several conditions are not easily identified with the available methods and/or the conclusive identification of a disease or condition may be reached too late for adequate corrective treatment.
Due to the extensive time often encountered in a complete diagnostic procedure, incorrect antibiotic therapy is often started prematurely, before a conclusive diagnosis is reached. This medical practice can aggravate the serious development of bacterial strains resistant to antibiotics.
Thus, even though a great number of differential diagnostic methods have been developed, there is still a considerable number of closely related conditions, or combinations of conditions that resist quick, safe and sure identification at low cost.
Furthermore, a number of diagnostic methods depend on the injection of foreign fluids or other kinds of transfer of diagnostic aids onto or into the organism under observation, or require biopsies. The removal of sample tissue from parts of the organisms often not easily accessible may also have a detrimental effect on the identification process and healing process itself.
It is known that certain diseases result in the elevated expression of different genes which may in some cases account for the pathogenicity of the disease or condition in question. Screening for the presence of a particular transcript as an indication of the presence of disease has thus been described (see for example Enderlin et al., FEBS Letters, (1997), 412, p629-632). Methods for quantifying the levels of different transcripts by binding to cDNA derived from gene libraries, or by sequencing and electronic comparison to other libraries has been described in for example Schena et al., (1996), PNAS USA, 93, p10614-10619; Schena et al., (1995), Science, 270, p467-470, Heller et al. (1997), PNAS USA, 94, p2150-2155 and International Patent Application No. WO95/20681.
However, a quick and simple method using the characteristic pattern of gene expression during disease or other conditions or stages thereof as a tool for diagnosis and/or prognosis, particularly a method which does not require any knowledge of the disease characteristics, the genes involved or their sequences has not been described.
It has now surprisingly been found that a simple method of diagnosis of a disease or condition or stage thereof may be performed by the preparation of a characteristic gene transcript pattern standard or fingerprint (standard diagnostic probe pattern) for that disease/condition followed by comparison of the transcript pattern of a patient or organism under study to that pattern. The standard is prepared by the identification of a number of specific and informative probes which serve as a set of markers for the disease or condition or stage thereof to be identified. These probes are bound to a solid support and then hybridized to mRNA, optionally reverse transcribed and/or amplified. The amount of the nucleic acid material which binds to the different probes is assessed and together forms the transcript pattern standard of that disease or condition or stage thereof.
Thus, in order to identify diseases, malaises or other conditions caused by other organisms, toxins, stress, ageing, environmental changes, etc, in human beings, animals, plants and all other living eukaryotic and prokaryotic organisms, a set of standard probe patterns of the amount of transcript from one or more informative genes relative to a standard may be developed, each such standard probe pattern being characteristic of one ailment or condition and/or stage of such ailment. These standard probe patterns are subsequently compared with a pattern of transcript levels, using the same probes, prepared from a recent sample of tissue or body fluid collected from a patient to be diagnosed, such patterns being specific to the present condition of the patient.
Usually the reaction to infections, toxins or deteriorations are accompanied by changes in the level of activity in several or many genes. These activity levels, that may either be relatively higher or lower, are together specific to the type of condition that is encountered. The normal activity and the altered activity may, to a large extent, be measured by the amount of specific transcript or mRNA that is present. Thus, standardised probes for analysis may be designed that have patterns of activity that are characteristic for each condition or combination of conditions that is to be identified or diagnosed. These standardised probes may be used to compare the standardised probe pattern with transcript patterns from samples of tissue or body fluids prepared in a similar way and obtained from a live patient or the organism to be studied.
In order to put the invention into practical use, two kinds of substantially similarly developed diagnostic probes must be available for comparison.
1. A standard diagnostic probe pattern (SDPP) that is characteristic of the suspected ailment, developed from one or more organisms having the condition or disease or stage thereof in question.
and
2. A patient specific probe pattern (PSPP) that is developed from a recently obtained sample of tissue or body fluid from a organism to be studied.
To apply the invention to a specific condition, the pattern of a SDPP characteristic of the suspect ailment or stage thereof must have been developed beforehand. In addition, a recent, well preserved sample of tissue or body fluid from the patient must be available to develop the PSPP, for comparison with one or several different SDPPs for the number of ailments and their different stages that is suspected.
To design and develop the pattern for SDPPs, characteristic for one ailment, known techniques of isolation of mRNA, construction and amplification of cDNA and selection through differential hybridisation and differential display may be used.
Selected informative mRNA or cDNA probes from one or more patients that have been conclusively diagnosed with the ailment in question are isolated and amplified. These SDPPs together will be used to compare if the PSPP is similar to the SDPP. Several such characteristic SDPPs may be developed to represent different stages of the same ailment.
The pattern of such standard probes for a great number of ailments and different stage of such ailments may be accumulated in databases and be made available to laboratories on request.
Thus, viewed from one aspect the present invention provides a method of preparing a gene transcript pattern probe kit for diagnosing or identifying a disease or condition or stage thereof in a prokaryotic or eukaryotic organism comprising at least the steps of:
a) isolating mRNA from the tissue, cells or body fluid of a normal prokaryotic or eukaryotic organism (normal sample);
b) isolating mRNA from the corresponding tissue, cells or bod
Lönneborg Anders
Sharma Praveen
Diagenic AS
Jones W. Gary
Sughrue & Mion, PLLC
Switzer Juliet C.
LandOfFree
Method of preparing a standard diagnostic gene transcript... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method of preparing a standard diagnostic gene transcript..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of preparing a standard diagnostic gene transcript... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3263744