What is PKS?
PKS stands for Pallister-Killian Syndrome. It is a genetic disorder discovered by a small group of doctors, including Dr. Philip Pallister and Dr. W. Killian. The clinical name for PKS is isochromosome aneuploidy mosaicism.
Children born with PKS have an extra set of the short arm of the 12th chromosome. While most children are born with 46 total chromosomes, PKS children are born with 47 total chromosomes. PKS is also mosaic – not all cells of a child diagnosed with PKS has the extra chromosome in every cell of their body. (For more information about chromosomes, read UNIQUE’s Little Yellow Book) Like many other genetic syndromes, PKS is not a hereditary condition — it is random and sporadic.
Some of the symptoms of PKS are:
- High arched palate
- Definitive hair pattern (even when a child has a full head of hair when born, they typically lose all hair but what is on the crown of their head and what is just above the nape of their neck)
- Breathing problems
- Diaphragmatic Hernias
- Skin Discoloration
- Low muscle tone
- Feeding problems
The amount of affected cells — or mosaicism — is not a factor in the amount of ability or disability. One child with 57% mosaicism attends honors classes, while another with 20% mosaicism is profoundly disabled.
