Mycobacterium tuberculosis specific DNA fragment

Details Mycobacterium tuberculosis specific DNA fragment Mycobacterium tuberculosis specific DNA fragment

1998-09-18

2001-06-05

Swartz, Rodney P. (Department: 1645)

Organic compounds -- part of the class 532-570 series

Organic compounds

Carbohydrates or derivatives

C424S168100, C424S185100, C424S191100, C424S248100, C435S070100, C435S017000, C435S091100, C435S253100, C530S300000, C530S350000, C536S023700, C536S024300, C536S024320

Reexamination Certificate

active

06242585

ABSTRACT:

FIELD OF INVENTION
This invention relates to a
Mycobacterium tuberculosis
specific DNA fragment containing IS like and repetitive sequences, a method of production of such DNA fragment and the use of such DNA fragment, for example, to rapidly diagnose
Mycobacterium tuberculosis
infection in clinical samples, and to identify clinical isolates of
Mycobacterium tuberculosis
. The DNA fragment may be used to determine information about the epidemiology of
Mycobacterium tuberculosis
infection. Specifically this invention relates to the use of sequence specific DNA fragments to diagnose
Mycobacterium tuberculosis
and strains of
Mycobacterium tuberculosis
. A purpose of the study of the epidemiology of tuberculosis is to distinguish the genetic diversity of the causative agent
Mycobacterium tuberculosis
and to obtain information about strain to strain variability. This can be achieved by molecular epidemiological methods including DNA fingerprinting and restriction fragment length polymorphism (RFLP) analysis. Such approaches, can aid the investigation of point source outbreaks, transmission, pathogenesis and may be employed as a marker of strain typing.
BACKGROUND OF THE INVENTION
Tuberculosis (TB) is a major cause of infectious mortality. According to a recent WHO report, the number of deaths attributed to TB was larger number in 1995 than in any other year in history (Moran, N. 1996. WHO Issues Another Gloomy Report. Nature Medicine 4:377). Tuberculosis remains widespread worldwide and constitutes a major health problem particularly in developing countries. One third of the total world's population (nearly two billion people) is infected with
Mycobacterium tuberculosis
out of which 5 to 10% develop the disease. TB causes more than 3 million deaths per year and recently WHO has predicted that 30 million people will die of TB in the next ten years (Joint International Union Against Tuberculosis and World Health Organization Study Group. Tubercl 63:157-169, 1982). Tuberculosis is caused by a gram positive acid fact bacterium
Mycobacterium tuberculosis
or
M. bovis
, which are the tubercle bacilli of the family of Mycobacteriaceae.
M. bovis
is a species which causes tuberculosis in cattle and can be transmitted to humans and other animals in which it causes tuberculosis. At present nearly all tuberculosis in humans is caused by
Mycobacterium tuberculosis
. Infections occasionally result from other species of mycobacteria that are common environmental saprophytes. These species have been collectively termed as MOTT (Mycobacteria other than typical tubercle), environmental or tuberculoid bacilli. The difference between the two infections is that infection with
Mycobacterium tuberculosis
is always transmitted from host to host. In contrast, human beings infected with other mycobacteria rarely transmit the disease.
Hence the essential component of any tuberculosis control program is containment of the disease. Identification of infected individuals, especially those most likely to transmit viable bacilli, comes as a first priority in strategies for tuberculosis control. Early and timely diagnosis of tuberculosis is essential for identifying individuals carrying the bacilli. Therefore a need has arisen for a method of diagnosis of tuberculosis which is rapid, sensitive and specific. Routine diagnostic methods used for identification of
Mycobacterium tuberculosis
includes acid fast smear test in clinical samples like sputum, tests based on growth of bacilli of specific media and differential biochemical tests. The culture of mycobacteria from clinical samples is the most reliable and provides for definite diagnosis of tuberculosis. Although 100% specific, it takes six to eight weeks due to slow growth of organisms and further biochemical testing before identification can be made (Heifests, L B. and Good, R. C. 1994. Current Laboratory Methods for the Diagnosis of Tuberculosis. Tuberculosis Pathogenesis, Protection and Control (ed. B. R. Bloom) ASM Washington D.C., pp. 85-110).
Methods based on antigen and antibody detection in body fluids and more recently nucleic acid probes (sequence specific DNA fragments) have been developed as reagents for rapid diagnosis and monitoring of the epidemiology of tuberculosis (Young, D. B. and Mehlert, A. 1989, Serology of Mycobacteria: Characterization of Antigens Recognized by Monoclonal Antibodies. Rev. Infec. Dis. 12: S431-S435; Pfyfer, G. E., Kisling, P., Jahn, E. M. I., Martin, H., Salfinger; W. M. and Weber, R. 1996. Diagnostic Performance of Amplified
Mycobacterium Tuberculosis
Direct Test with Cerebrospinal Fluid, Other Non Respiratory and Respiratory Specimens, J. Clin. Microbiol. 34:834-841).
The DNA probes utilize a wide array of sequences from
Mycobacterium tuberculosis
ranging from whole genomic DNA, to a single copy sequence, and to repetitive DNA elements. When evaluated directly on clinical samples they have proved to be highly specific, sensitive and dramatically reduce the time for diagnosis of tuberculosis (Kiehn, T. E. 1993. The Diagnostic Mycobacteriology Laboratory of the 1990's. Clin. Infect. Dis. 17 (suppl.2) S447-S454).
Several sequence specific probes have been used as targets for identification of
Mycobacterium tuberculosis
by amplification of specific sequences by PCR.
IS6110 is an IS element present in members of
Mycobacterium tuberculosis
complex (
Mycobacterium tuberculosis, M. bovis, M. africanum
, and
M. microti
).
Different regions of IS6110 have been amplified using different sets of primers for PCR based diagnosis like 123 base pair (bp) or 245 bp region (Einsenach, K. D., Cave, M. D., Bates, J. H. and Crawford, J. T. 1990. Polymerase chain reaction amplification of repetitive DNA sequence specific for
Mycobacterium tuberculosis
. J. Infect. Dis. 161:977-981; Kolk, A. H. J., Schuitema, A. R. J., Kuijper, S., VanLeeuwen J., Hermans, P. W. M., Van Embden, J. D. A. Hartskeerl, R. A. 1992, Detection of
Mycobacterium tuberculosis
in clinical samples by using polymerase chain reaction and a non radioactive detection system. J. Clin. Microbiol. 30:2567-2575).
IS6110 has some disadvantages. Several
Mycobacterium tuberculosis
strains with one copy or no copy of IS6110 have been reported (Sahadevan, R., Narayanan, S. Paramsivam, C. N., Prabhakar, R. and Narayanan, P. R. 1995. Restriction fragment length polymorphism typing of clinical isolates of
Mycobacterium tuberculosis
from patients with pulmonary tuberculosis in Madras, India by use of direct repeat probe. J. Clin. Microbiol. 33:3037-3039: Van Soolingen, D., Dehass, P. E. W., Hermans, P. W. M. Groenen, P. M. A. and Van Embden, J. D. A. 1993. Comparison of various repetitive DNA elements as genetic markers for strain differentiation and epidemiology of
Mycobacterium tuberculosis
. J. Clin. Microbiol. 31:1987-1995). Thus the repertoire of
Mycobacterium tuberculosis
strains present all over the world may not be selected/amplified using a single repetitive element or one DNA probe specific to
Mycobacterium tuberculosis
. The search for newer DNA probes is a constant requirement.
OBJECTS OF THE INVENTION
It is an object of this invention to detect
Mycobacterium tuberculosis
in a clinical sample.
It is another object of this invention to describe a DNA fragment containing IS like sequence and repetitive sequences.
It is a further object of this invention to use a DNA fragment containing IS like sequence and repetitive sequences to detect
Mycobacterium tuberculosis.
It is yet another object of this invention to describe a method for production of a DNA fragment containing IS like sequence and repetitive sequences.
It is another object of this invention to use a 1291 base pair sequence having an IS like sequence and repetitive sequences or a portion or fragment of the 1291 base pair sequence to detect
Mycobacterium tuberculosis.
It is a further object of this invention to construct a sequence specific DNA probe for the identification of
Mycobacterium tuberculosis
present in clinical samples.
It is another object of this i

Affiliated with

Also associated with

Rating

Mycobacterium tuberculosis specific DNA fragment does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Mycobacterium tuberculosis specific DNA fragment, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Mycobacterium tuberculosis specific DNA fragment will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2461599