I am a human geneticist investigating several diseases caused by abnormalities of human chromosomes, particularly chromosome 22. Changes in the genes on this chromosome can cause developmental abnormalities and mental retardation. With my colleagues, I have determined that the majority of patients with DiGeorge Syndrome (DGS) and Velocardiofacial Syndrome (VCFS) carry a deletion of the same region of chromosome 22. We also developed the standard diagnostic test, used by labs worldwide, to assess the presence of a deletion and the likelihood of recurrence of deletion-based DGS/VCFS. We are also investigating the duplication of genes on this chromosome that give rise to other chromosomal disorders such as Supernumerary der(22) Syndrome. These studies will provide greater insight into the causes of some genetic diseases.
In the laboratory, we are conducting molecular analyses of deletion and translocation breakpoint regions. We continue to analyze the t(11;22)(q23;q11), the only recurrent non-Robertsonian constitutional translocation in man. We have finally isolated and examined the breakpoint of the t(11;22). The identification of unusual DNA structures (palindromic AT-rich repeats) at the breakpoints suggest a mechanism for the instability of chromosomes 11 and 22 as well as the molecular similarity of the breakpoint region in numerous unrelated families. The role of these sequences in other translocations of
chromosome 22 is being investigated. Further, we are examining the physical arrangements and rearrangements of chromosome 11 and 22 during meiosis. Techniques such as fluorescence in situ hybridization, PCR, Southern blot and pulsed-field gel electrophoresis are among the many techniques used in my laboratory to investigate the etiology of various chromosomal disorders.
Nimmakayalu MA., Gotter AL., Shaikh TH., Emanuel BS.: A novel sequence-based approach to localize translocation breakpoints identifies the molecular basis of a t(4;22). Human Molecular Genetics 12(21): 2817-25, Nov 1 2003.
DeBerardinis RJ., Conforto D., Russell K., Kaplan J., Kollros PR., Zackai EH., Emanuel BS.: Myoclonus in a patient with a deletion of the epsilon-sarcoglycan locus on chromosome 7q21. American Journal of Medical Genetics 121A(1): 31-6, Aug 15 2003.
McElhinney DB., Driscoll DA., Emanuel BS., Goldmuntz E.: Chromosome 22q11 deletion in patients with truncus arteriosus. Pediatric Cardiology 24(6): 569-73, Nov-Dec 2003.
McElhinney DB., Driscoll DA., Levin ER., Jawad AF., Emanuel BS., Goldmuntz E.: Chromosome 22q11 deletion in patients with ventricular septal defect: frequency and associated cardiovascular anomalies. Pediatrics 112(6 Pt 1): e472, Dec 2003.
Kurahashi H., Shaikh T., Takata M., Toda T., Emanuel BS.: The constitutional t(17;22): another translocation mediated by palindromic AT-rich repeats. American Journal of Human Genetics 72(3): 733-8, Mar 2003.
Gripp KW., Kasparcova V., McDonald-McGinn DM., Bhatt S., Bartlett SP., Storm AL., Drumheller TC., Emanuel BS., Zackai EH., Stolle CA.: A diagnostic approach to identifying submicroscopic 7p21 deletions in Saethre-Chotzen syndrome: fluorescence in situ hybridization and dosage-sensitive Southern blot analysis. Genetics in Medicine 3(2): 102-8, Mar-Apr 2001.
Gong W., Gottlieb S., Collins J., Blescia A., Dietz H., Goldmuntz E., McDonald-McGinn DM., Zackai EH., Emanuel BS., Driscoll DA., Budarf ML.: Mutation analysis of TBX1 in non-deleted patients with features of DGS/VCFS or isolated cardiovascular defects. Journal of Medical Genetics 38(12): E45, Dec 2001.
Kurahashi H., Emanuel BS.: Long AT-rich palindromes and the constitutional t(11;22) breakpoint. Human Molecular Genetics 10(23): 2605-17, Nov 1 2001.
Kurahashi H., Emanuel BS.: Unexpectedly high rate of de novo constitutional t(11;22) translocations in sperm from normal males. Nature Genetics 29(2): 139-40, Oct 2001.
Emanuel BS., Shaikh TH.: Segmental duplications: an 'expanding' role in genomic instability and disease. [Review] [91 refs] Nature Reviews Genetics 2(10): 791-800, Oct 2001.
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Last updated: 08/22/2014
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