Prader Willi and Angelman Syndrome are neurodevelopmental disorders caused by a deletion of a region in chromosome 15 and are classically known as genomic imprinting disorders. These disorders are characterized by an imprinting center controlling the expression of selected genes in chromosome 15, therefore a deletion in these areas affect the expression of certain genes. Depending on the deletion occurring in the maternal or paternal chromosome the resulting disorder is Prader Willi if occurring in the paternal chromosome, or Angelman Syndrome if occurring in the maternal chromosome. Prader Willi Syndrome is caused by paternal deletion or maternal uniparental disomy of chromosome 15 and it is commonly characterized by diminished fetal activity, obesity, hypotonia, intellectual disability, short stature etc. Angelman Syndrome is originated from maternal deletion or paternal uniparental disomy and is characterized by jerky movements, abnormal laugher, sleep disturbances and characteristic facial features.
The Igenomix Prader Willi and Angelman Syndrome Precision Panel can be used for an accurate and directed diagnosis ultimately leading to a better management and prognosis of the disease. It provides a comprehensive analysis of the genes involved in this disease using next-generation sequencing (NGS) to fully understand the spectrum of relevant genes involved.
The clinical utility of this panel is:
|
GENE |
OMIM DISEASES |
INHERITANCE* |
% GENE COVERAGE (20X) |
HGMD** |
|
HERC2 |
Autosomal |
AD,AR |
98.91 |
9 of 9 |
|
IPW |
Prader-Willi |
AD |
– |
– |
|
MAGEL2 |
Prader-Willi |
AD |
99.99 |
43 of 48 |
|
MBD5 |
Autosomal |
AD |
99.99 |
33 of 35 |
|
MKRN3 |
Prader-Willi |
AD,AD,MI |
99.98 |
39 of 41 |
|
MKRN3-AS1 |
Prader-Willi |
AD |
– |
– |
|
NDN |
Prader-Willi |
AD |
97.41 |
2 of 2 |
|
NPAP1 |
Prader-Willi |
AD |
99.82 |
– |
|
PWAR1 |
Prader-Willi |
AD |
– |
– |
|
PWRN1 |
Prader-Willi |
AD |
– |
– |
|
SIM1 |
6q16 |
– |
99.64 |
39 of 40 |
|
SLC9A6 |
X-linked |
X,XD,G |
98.87 |
– |
|
SNORD115-1 |
Prader-Willi |
AD |
– |
– |
|
SNORD116-1 |
Prader-Willi |
AD |
– |
– |
|
SNRPN |
Prader- |
AD,MU |
100 |
2 of 2 |
|
UBE3A |
Angelman |
AD |
99.98 |
208 of 211 |
* Inheritance: AD: Autosomal Dominant; AR: Autosomal Recessive; X: X linked; XLR: X linked Recessive; Mi: Mitochondrial; Mu: Multifactorial; G: Gonosomal Inheritance; D: Digenic Inheritance
** HGMD: Number of clinically relevant mutations according to HGMD
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