Duplication of chromosome band 12q24.11q24.23 results in apparent Noonan syndrome

@article{Shchelochkov2008DuplicationOC,
  title={Duplication of chromosome band 12q24.11q24.23 results in apparent Noonan syndrome},
  author={Oleg A. Shchelochkov and Ankita Patel and George M. Weissenberger and A. Craig Chinault and Joanna Wiszniewska and Priscilla H. Fernandes and Christine M. Eng and Mary K Kukolich and Vernon Reid Sutton},
  journal={American Journal of Medical Genetics Part A},
  year={2008},
  volume={146A}
}
Noonan syndrome is an autosomal dominant disorder with an estimated incidence of 1 in 1,000 to 1 in 2,500 live births. It is characterized by postnatal‐onset short stature, characteristic facial changes, webbed neck, pectus carinatum, or excavatum, congenital heart defects, and bleeding abnormalities. Gain‐of‐function mutations in the PTPN11, KRAS, SOS1, and RAF1 genes that are components of the RAS/MEPK signaling pathway are identified in about 70–85% of individuals with Noonan syndrome. We… 
Microduplication of 3p25.2 encompassing RAF1 associated with congenital heart disease suggestive of Noonan syndrome
TLDR
It is suggested that duplications of genomic regions encompassing RAF1 could cause Noonan syndrome and are consistent with the notion that rare copy number variations encompassing causative genes may underlie a small percentage of patients with syndromic CHD like NS.
Molecular characterization of a balanced rearrangement of chromosome 12 in two siblings with Noonan syndrome
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Genomic duplication of PTPN11 is an uncommon cause of Noonan syndrome
TLDR
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Copy number variants and rasopathies: germline KRAS duplication in a patient with syndrome including pigmentation abnormalities
TLDR
A syndromic familial case of a 12p duplication encompassing the dosage sensitive gene KRAS, whose phenotype overlapped with rasopathies is reported, a class of rare genetic syndromes combining facial abnormalities, heart defects, short stature, skin and genital abnormalities, and mental retardation.
7q Deletion/12q Duplication Is the Possible Cause of an Alobar Holoprosencephaly Case
TLDR
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Rare copy number variations containing genes involved in RASopathies: deletion of SHOC2 and duplication of PTPN11
TLDR
This is the first report suggesting that haploinsufficiency of SHOC2 can result in a RASopathy-like phenotype, and provides additional support that copy number variations containing disease-causing genes of RAS/MAPK pathway play a minor role in RASopathies or related disorders.
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