Chemistry: molecular biology and microbiology – Measuring or testing process involving enzymes or... – Involving nucleic acid
Reexamination Certificate
1997-03-18
2002-08-13
Jones, W. Gary (Department: 1655)
Chemistry: molecular biology and microbiology
Measuring or testing process involving enzymes or...
Involving nucleic acid
C435S810000, C436S501000, C536S027400
Reexamination Certificate
active
06432635
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention is directed to a genetic sequence that has been identified as the locus of mutations that cause epilepsy and to methods for the diagnosis of this disease and for the detection of the presence of the mutated gene as an indication of potential for genetic transmission of a disease.
BACKGROUND
Cystatin B is a small protein that is a member of a superfamily of cysteine protease inhibitors, which are generally grouped into three families based on structural relationships—stefins (of which cystatin B is a member), cystatins and kininogens (Jarvinen, M. et al.,
Biochim. Biophys. Acta
708:210-217 (1982); Turk, V. et al.,
FEBS Lett
285:213-219 (1991)). It is a tightly-binding reversible inhibitor of cathepsins L, H and B, is found in all tissues, and is thought to inactivate proteases that leak out of the lysosome (Jarvinen, M. et al., (1982); Turk, V. et al., (1991); Ritonja, A. et al.,
Biochem. Biophys. Res. Commun
. 131:1187-1192 (1985); Jerala, R. et al.,
FEBS Lett
239:41-44 (1988)). Its amino acid sequence in humans is known (Jarvinen, M. et al., (1982); Turk, V. et al., (1991)). Another member of this family of protease inhibitors, cystatin C, has been shown to be responsible for hereditary cerebral amyloid angiopathy (Abrahamson, M. et al.,
Hum. Genet
. 82:223-226 (1989); Ghiso, J. et al.,
Proc. Natl. Acad. Sci. U.S.A
. 83:2974-2978 (1986)). This dominantly-inherited disease is characterized by the deposition of cystatin C-rich amyloid fibrils in affected brain arteries.
Progressive myoclonus epilepsy refers to a heterogeneous group of severe inherited epilepsies that are characterized by myoclonic seizures, generalized epilepsy and progressive neurological deterioration, including dementia and ataxia (Berkovic, S. F. et al.,
N. Enql. J. Med
. 315:296-305 (1986)). One of the five recognized members of this class is progressive myoclonus epilepsy of the Unverricht-Lundborg type (EPM1; H. Unverricht,
Die Myoclonie
(Franz Deuticke, Vienna), pp. 1-128 (1891); H. Unverricht,
Disch, Z. Nervenheilk
7:32-67 (1895); H. Lundborg, Die Proqressive Mvoclonus-Epilepsie (
Unverrichts Myoklonie
) Almquist & Wiksell, Uppsala, pp. 1-207 (1903). This form of epilepsy is inherited as an autosomal recessive disease in which patients have severe stimulus-sensitive myoclonus and tonic-clonic seizures beginning between ages 6 and 15, and have a variable rate of progression between and within families (Koskiniemi, M.,
Epilepsia
15:537-545 (1974); Koskiniemi, M. et al.,
Acta Neurol. Scandinav
. 50:333-359 (1974); Koskiniemi, M. et al.,
Acta Neurol. Scandinav
. 5:307-332 (1974); Norio, R. et al.,
Clin Genet
. 15:382-384 (1979)). Seizures tend to diminish at 25-30 years of age, although mild dementia generally develops late in the course of the disease. Unlike the other progressive myoclonus epilepsies, inclusion bodies or storage material are not observed in EPM1, and diagnosis of the disease is usually based on clinical history, typical electroencephalographic abnormalities, and the exclusion of the other four subtypes (Lafora's disease, MERRF syndrome, neuronal ceroid lipofuscinosis and sialidosis); EPM1 and other forms of epilepsy affect about 3% of the world's population (Scheuer, M. L. et al.,
N. Enql. J. Med
. 323:1468-1474 (1990)).
The genes responsible for Lafora's disease and juvenile myoclonus epilepsy, which have symptoms similar to EPM1, have been localized to specific chromosomal regions by meiotic linkage analysis (Serratosa, J. M. et al.,
Hum. Mol. Genet
. 4:1657-1663 (1995); Greenberg, D. A. et al.,
Am. J. Med. Genet
. 31:185-192 (1988); Liu, A. W. et al.,
Am. J. Hum. Genet
. 57:68-381 (1995)). Linkage analysis initially localized the gene responsible for EPM1 to a 2 million base pair (Mb) region on the long arm of human chromosome 21 between the DNA markers CBS and CD18 (Lehesjoki, A. E. et al.,
Proc. Natl. Acad. Sci. U.S.A
. 883696-3699 (1991); Lehesjoki, A. E. et al. Neurolocv 42:1545-1550 (1992); Lehesjoki, A. E. et al.,
Hum. Molec. Genet
. 2:1229-1234 (1993)). However, prior to the current elucidation of a molecular defect for cystatin B, no specific defects have been found to be associated with EPM1.
SUMMARY OF THE INVENTION
One aspect of the invention is an isolated nucleic acid molecule, wherein said molecule comprises:
(1) a first sequence consisting of human cystatin B genomic DNA as set forth in
FIG. 3
(SEQ ID NO:1);
(2) a second sequence, wherein said second sequence is a subsequence of said first sequence, is at least 10 nucleotides in length, and is not present in human cystatin B cDNA;
(3) a third sequence in which at least one nucleotide of said first or second sequences is replaced by a different nucleotide; or
(4) a fourth sequence complementary to any of said first, second or third sequences;
with the proviso that (I) if said molecule is an RNA molecule, U replaces T in said sequence of said molecule, and (ii) said third sequence is at least 95% identical to said first or second sequence.
Another aspect of the invention is an isolated nucleic acid molecule, wherein said molecule comprises a first sequence in which at least one nucleotide of cystatin B cDNA is replaced by a different nucleotide or a second sequence complementary to said first sequence, with the proviso that (I) if said molecule is an RNA molecule, U replaces T in said sequence of said molecule and (ii) said first sequence is at least 95% identical to cystatin B cDNA.
Another aspect of the invention is a method of detecting the presence of a genetic defect that causes epilepsy in a human or that can transmit epilepsy to an offspring of said human which comprises:
identifying a mutation of a cystatin B gene of said human, wherein said mutation provides a cystatin B gene sequence different from human cystatin B genomic DNA sequence as set forth in
FIG. 3
(SEQ ID NO:1).
Another aspect of the invention is a method for treating an individual with progressive myoclonus epilepsy, comprising supplying to said individual an effective amount of a gene product of a cystatin B gene.
REFERENCES:
patent: 5124246 (1992-06-01), Urdea et al.
patent: 5223409 (1993-06-01), Ladner et al.
patent: 5270170 (1993-12-01), Schatz et al.
patent: 5283185 (1994-02-01), Epand et al.
patent: 5288609 (1994-02-01), Engelhardt et al.
Abrahamson, M. et al., “The human cystatin C gene (CST3), mutated in hereditary cystain C amyloid angiopathy, is located on chromosome 20,”Hum. Genet. 82:223-226 (1989).
Appel, J.R. et al., “Elucidation of Discontinuous Linear Determinants in Peptides,”J. Immunology144(3): 976-983 (1990).
Berkovic, S.F. et al., “Progressive myoclonus epilepsies: Specific causes and diagnosis,”N. Engl. J. Med. 315(5):296-305 (1986).
Felgner, P.L. et al., “Lipofection: A highly efficient, lipid-mediated DNA-transfection procedure,”Proc. Natl. Acad. Sci. U.S.A. 84:7413-7417 (1987).
Ghiso, J. et al., “Amyloid fibrils in hereditary cerebral hemorrhage with amyloidosis of Icelandic type is a variant of &ggr;-trace basec protein (cystatin C)”Proc. Natl. Acad. Sci. U.S.A. 83:2974-2978 (1986).
Greenberg, D.A. et al., “Juvenile myoclonic epilepsy (JME) may be linked to the BG and HLA loci on human chromosome 8,”Am. J. Med. Genet. 31:185-192 (1988).
Ichikawa, H. et al., “A NotI restriction map of the entire long arm of human chromosome 21,”Nature Genetics4:361-366 (1993).
Järvinen, M. et al., “Human spleen cysteineproteinase inhibitor,”Biochem Biophys Acta708:210-217 (1982).
Jerala, R. et al., “Clonging a synthetic gene for human stefin B and its expression inE. coli,”FEB239(1):41-44 (1988).
Jerala, R. et al., “Deletion of the carboxy terinal part of stefin B does not have a major effect for binding to papain,”Biomed. Biochim. 50:627-629 (1991).
Jou, Y.S et al., “Localization of the &agr;2-Macroglobulin Receptor-Associated Protein 1 Gene (LRPAP1) and other Gene Fragments to Human Chromosome 4p16.3 by Direct cDNA Selection,”Genomics24:410-413 (1994).
Koskiniemi, M., “Psychological Findings in Progressive Myoclonus Epilepsy Without Lafora Bodies,”Epil
Cox David R.
De La Chapelle Albert
Lehesjoki Anna-Elina
Myers Richard M.
Pennacchio Len A.
Borden Paula A.
Bozicevic Field & Francis LLP.
Field Bret E.
Helsinki University Licensing Ltd. Oy
Jones W. Gary
LandOfFree
Cystatin B mutants does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Cystatin B mutants, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cystatin B mutants will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2880337