Conflicts of interest: None.
Article first published online: 7 JUN 2012
Copyright © 2012 Wiley Periodicals, Inc.
American Journal of Medical Genetics Part A
Volume 158A, Issue 7, pages 1765–1770, July 2012
How to Cite
Gregor, A., Krumbiegel, M., Kraus, C., Reis, A. and Zweier, C. (2012), De novo triplication of the MAPT gene from the recurrent 17q21.31 microdeletion region in a patient with moderate intellectual disability and various minor anomalies. Am. J. Med. Genet., 158A: 1765–1770. doi: 10.1002/ajmg.a.35427
How to Cite this Article: Gregor A, Krumbiegel M, Kraus C, Reis A, Zweier C. 2012. De novo triplication of the MAPT gene from the recurrent 17q21.31 microdeletion region in a patient with moderate intellectual disability and various minor anomalies. Am J Med Genet Part A. 158A:1765–1770.
- Issue published online: 18 JUN 2012
- Article first published online: 7 JUN 2012
- Manuscript Accepted: 26 MAR 2012
- Manuscript Received: 7 JAN 2012
- DFG. Grant Number: Zw184/1-1
- microdeletion 17q21.31;
- mental retardation;
- intellectual disability
We report on a 16-year-old male patient with moderate intellectual disability, behavioral problems, and further anomalies such as facial dysmorphism, heart defect, and urogenital anomalies. By molecular karyotyping we identified the first de novo copy number gain to four copies on chromosome 17q21.31 including the MAPT gene but not the entire recurrent microdeletion/microduplication region. Recurrent microdeletions of this region including the MAPT and the CHRH1 genes have been shown to be a relatively frequent cause of intellectual disability, while only a few reciprocal duplications in patients with variable cognitive disorders have been published so far. A common inversion polymorphism in this region has been linked to a distinct H2 haplotype and seems to be associated with an increased risk for microdeletions and -duplications. Our patient and his father were both heterozygous for the H1/H2 haplotype, whereas the mother was homozygous for the H2 haplotype. In our patient the dosage gain apparently occurred on the paternal H1 allele and did not involve the H2 allele as in the previously published cases. This patient further delineates the genotypic and phenotypic variability associated with copy number variants from the 17q21.31 microdeletion region. © 2012 Wiley Periodicals, Inc.