Potocki-Lupski Syndrome (PTLS)
Potocki-Lupski Syndrome (PTLS) is a recently discovered condition linked to a duplication of chromosome 17p11.2, which can cause a number of health problems including developmental delay, speech problems, feeding difficulties, sleep apnea, autism, hyperactivity and low muscle tone.
What are the clinical features of PTLS?
- Low muscle tone since infancy
- Feeding problems, e.g. difficulty chewing or swallowing or both
- Developmental Delay
- Verbal Apraxia (speech delay caused by motor-planning issues)
- Sleep Apnea (does your child wake up early or in the middle of the night?)
- Autism Spectrum Disorder: autism, Asperger Syndrome or PDD-NOS
- Potential Heart Defects
The above mentioned clinical features of PTLS will change over time as the child grows and develops.
How is PTLS diagnosed?
Parents need to talk to their child’s health care provider to schedule a genetic testing that will determine if the duplication of 17p11.2 is present. A diagnosis of PTLS may be given if a duplication of 17p11.2 is found in combination with some of the symptoms of PTLS. To evaluate potential heart problems, an electrocardiogram and/or an echocardiogram could be performed. A sleep study may be also be performed if your child seems to have sleeping problems (is waking up early) to rule out sleep apnea.
Many Genes Duplicated, but 1 gene seems to “jump out”
The duplicated region of chromosome 17 contains many genes, but studies with transgenic mice have revealed that one gene in particular seems to be responsible for the majority of the clinical features of PTLS and the associated chromosome 17 deletion syndrome, Smith-Magenis Syndrome. This gene, RAI1 (Retenoic Acid Inducible 1) causes physical and neurobehavioral abnormalities when the RAI1 gene copy number is either too low (deletion) or too high (duplication, PTLS).
How is Potocki-Lupski Syndrome (PTLS) treated?
Because PTLS is a multi-factorial condition, parents should talk to their health care provider about the multiple therapies that are available. This is usually arranged through your area’s early childhood intervention program. Therapies may include speech therapy for verbal apraxia, occupational therapy to address low muscle tone and possible sensory integration issues, and behavioral therapy.
Dietary intervention may also be helpful for many children with Potocki-Lupski Syndrome. This includes a gluten and casein free diet plus a diet free of food colorings. Parents have reported great success in treating verbal apraxia with fish oils. Parents may also consider our PureChild autism supplement (available soon).
Molina, J. et al. (2008) Abnormal social behaviors and altered gene expression rates in a mouse model for Potocki-Lupski syndrome. Hum Mol Genet. 17: 2486-95.
Martin, J. et al. (2008) Potocki-Lupski syndrome mimicking a connective tissue disorder. Clin Dysmorphol. 17: 211-13.
Potocki, L. et al. (2007) Characterization of Potocki-Lupski syndrome (dup(17)(p11.2p11.2)) and delineation of a dosage-sensitive critical interval that can convey an autism phenotype. Am J Hum Genet. 80: 633-49.
Bi, W. et al. (2007) Rai1 deficiency in mice causes learning impairment and motor dysfunction, whereas Rai1 heterozygous mice display minimal behavioral phenotypes. Hum Mol Genet. 16: 1802-13.
Walz, K. et al. (2006) Rai1 duplication causes physical and behavioral phenotypes in a mouse model of dup(17)(p11.2p11.2). J Clin Invest. 116: 3036-41.
Disclaimer: The above information is for educational purposes only and is not intended to substitute medical advice or care. Always consult a health care professional about any health problems or illnesses that you or your child may have.