#PWS is caused by a loss of function of genes on chromosome 15. These genes are peculiar, because they are in normal condition always expressed only from the paternal allele, the allele which is coming from the father, and not from both maternal and alleles – due to an epigenetic phenomenon called #GenomicImprinting. PWS patients either have parts of the paternal allele deleted or they have maternal uniparental disomy (#UPD) – a condition with effectively two maternal alleles instead of paternal and maternal alleles. This leads to a condition where some genes are not expressed at all, thus, their proteins and functions are missing for the proper development and functioning of the human body.

#PraderWilliSyndrome #RareDisease