Chemistry: molecular biology and microbiology – Measuring or testing process involving enzymes or... – Involving nucleic acid
Reexamination Certificate
1998-02-04
2001-05-29
Martinell, James (Department: 1633)
Chemistry: molecular biology and microbiology
Measuring or testing process involving enzymes or...
Involving nucleic acid
C536S024300
Reexamination Certificate
active
06238863
ABSTRACT:
CROSS-REFERENCE TO RELATED APPLICATIONS
Not Applicable.
FIELD OF THE INVENTION
The present invention is generally directed to the identification and analysis of genetic markers in a genomic system. The present invention is more specifically directed to the identification of loci in DNA, particularly in genomic DNA, containing length polymorphisms due to variations in the number of intermediate (5 to 7 base) sequence repeats. The present invention is also directed to the detection of such polymorphic loci. The invention is directed, furthermore, to methods of identifying and distinguishing individuals based primarily on differences in size of the products of amplifying genomic DNA at such a locus, wherein the number of intermediate tandem repeat sequences vary from one individual to another.
BACKGROUND OF THE INVENTION
DNA typing is commonly used to identify the parentage of human children, and to confirm the lineage of horses, dogs, and other prize animals. DNA typing is also commonly employed to identify the source of blood, saliva, semen, and other tissue found at a crime scene. DNA typing methods in use today are designed to detect and analyze differences in the length and/or sequence of one or more regions of DNA known to appear in at least two different forms in a population. DNA typing is also employed in clinical settings to determine success or failure of bone marrow transplantation and presence of particular cancerous tissues. Such length and/or sequence variation is referred to as “polymorphism.” Any region (i.e. “locus”) of DNA in which such a variation occurs is referred to as a “polymorphic locus.” Most DNA typing techniques employ at least one “marker” containing the at least one such polymorphic locus. Each individual marker contains a single allele of genomic DNA ultimately derived from a single individual in a population. The methods and materials of the present invention are all designed for use in the detection of a particular class of polymorphisms in DNA characterized primarily by variation in length.
Genetic markers which are sufficiently polymorphic with respect to length or sequence have long been sought for use in identity applications, such as paternity testing and identification of tissue samples collected for forensic analysis. The discovery and development of such markers and methods for analyzing such markers have gone through several phases of development over the last several years. In recent years, the discovery and development of polymorphic short tandem repeats (STRs) as genetic markers has stimulated progress in the development of linkage maps, the identification and characterization of diseased genes, and the simplification and precision of DNA typing. The term “short tandem repeat” or “STR” as used herein refers to all sequences between two and seven nucleotides long which are repeated perfectly, or nearly perfectly in tandem within the genomic DNA of any organism. See, for example, the definition of “short tandem repeat” applied to human genomic DNA in U.S. Pat. No. 5,364,759, column 4, line 58 et seq.
The first identified DNA variant markers were simple base substitutions, i.e. simple sequence polymorphisms, which were most often detected by Southern hybridization assays. For examples of references describing the identification of such markers, designed to be used to analyze restriction endonuclease-digested DNA with radioactive probes, see: Southern, E. M. (1975), J. Mol. Biol. 98(3):503-507; Schumm, et al. (1988),
American Journal of Human Genetics
42:143-159; and Wyman, A. and White, R. (1980)
Proc. Natl. Acad. Sci, U.S.A.
77:6754-6758.
The next generation of markers were size variants, i.e. length polymorphisms, specifically “variable number of tandem repeat” (VNTR) markers (Nakamura Y., et al. (1987),
Science
235: 1616-1622; and U.S. Pat. No. 4,963,663 issued to White et al. (1990); U.S. Pat. No. 5,411,859 continuation of U.S. Pat. No. 4,963,663 issued to White et al. (1995)) and “minisatellite” markers (Jeffreys et al. (1985a),
Nature
314:67-73; Jeffreys et al. (1985b)
Nature
316:76-79., U.S. Pat. No. 5,175,082 for an invention by Jeffreys). Both VNTR and minisatellite markers, contain regions of nearly identical sequences repeated in tandem fashion. The core repeat sequence is 10 to 70 bases in length, with shorter core repeat sequences referred to as “minisatellite” repeats and longer repeats referred to as VNTRs. Different individuals in a human population contain different numbers of these repeats. These markers are more highly polymorphic than base substitution polymorphisms, sometimes displaying up to forty or more alleles at a single genetic locus. However, the tedious process of restriction enzyme digestion and subsequent Southern hybridization analysis are still required to detect and analyze most such markers.
The next advance involved the joining of the polymerase chain reaction (PCR) (U.S. Pat. No. 4,683,202 by Mullis, K. B.) technology with the analysis of VNTR loci (Kasai K, et al. (1990) Journal Forensic Science 35(5):1196-1200). Amplifiable VNTR loci were discovered, which could be detected without the need for Southern transfer. The amplified products are separated through agarose or polyacrylamide gels and detected by incorporation of radioactivity during the amplification or by post-staining with silver or ethidium bromide. However, PCR can only be used to amplify relatively small DNA segments reliably, i.e. only reliably amplifying DNA segments under 3,000 bases in length Ponce, M & Micol, L. (1992) NAR 20(3):623; Decorte R, et al. (1990) DNA Cell Biol. 9(6):461-469). Consequently, very few amplifiable VNTRs have been developed, making them, as a class, impractical for linkage mapping.
With the recent development of polymorphic markers with polymorphic dinucleotide repeats (Litt and Luty (1989)
Am J. Hum Genet
3(4):599-605; Tautz, D (1989)
NAR
17:6463-6471; Weber and May (1989)
Am J Hum Genet
44:388-396; German Pat. No. DE 38 34 636 C2, inventor Tautz, D; U.S. Pat. No. 5,582,979 filed by Weber, L.) and with polymorphic short tandem repeats (STR) (Edwards, A., et al. (1991)
Am. J. Hum. Genet.
49: 746-756.; Hammond, H. A., et al. (1994)
Am. J. Hum. Genet.
55:175-189; Fregeau, C. J.; and Fourney, R. M. (1993)
BioTechniques
15(1): 100-119.; Schumm, J. W. et al. (1994) in
The Fourth International Symposium on Human Identification
1993, pp.177-187; and U.S. Pat. No. 5,364,759 by Caskey et al.; German Pat. No. DE 38 34 636 C2 by Tautz, D.) many of the deficiencies of previous methods have been overcome. The two types of markers, those containing dinucleotide or STR repeats (which by definition include 2-7 bp repeats), are generally referred to as “microsatellite” markers. Often considered to be the best available markers, the microsatellite loci are similar to amplifiable VNTRs, in that their alleles may be differentiated based on length variation. However, unlike VNTRs, these loci contain perfect or imperfect repeat sequences two, three, four, or rarely, five bases long. They display from just a few alleles to more than forty at a single locus. Amplification protocols can be designed to produce small products, generally from 60 to 400 base pairs long, and alleles from each locus are often contained within a range of less than 50 bp. This allows simultaneous electrophoretic analysis of several systems on the same gel by careful design of PCR primers such that all potential amplification products from an individual system do not overlap the range of alleles of other systems in the same gel.
Three significant drawbacks relate to the use of microsatellite loci. First, the presence of stutter artifacts, that is, one or more minor fragments in additional to the major fragment representing each allele, is often seen following amplification. This deficiency is much more severely displayed with dinucleotide repeat loci than with tri- or tetranucleotide repeat markers (Edwards et al., 1991. Am J Hum Genet 49;746-756; Edwards et al., 1992. Genomics 12:241-253; Weber & May, 1989. Am J Hum Genet 44:388-396
Bacher Jeffery W.
Schumm James W.
Frenchick Grady J.
King Karen B.
Martinell James
Michael & Best & Friedrich LLP
Promega Corporation
LandOfFree
Materials and methods for indentifying and analyzing... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Materials and methods for indentifying and analyzing..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Materials and methods for indentifying and analyzing... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2503250