The hereditary disease ponto cerebellar hypoplasia (PCH) occurs when certain areas of the brain do not develop properly; this results in severe mental and physical developmental disorders. Life expectancy of those affected ranges from a few months to a few years.
Scientists from Cologne and Amsterdam have discovered the mutations in human genetics which cause PCH of the types 2 and 4.
“In the case of PCH, the protein complex – the so-called tRNA-Splicing-Endonuclease, is mutated. This complex in involved in the manufacture of proteins in the human body and was identified in connection with a disease for the first time,” reports Birgit Budde from the Cologne Center for Genomics and Institute for Genetics of the University of Cologne.
PCH2 was first described as a syndrome in 1990 with reference to persons affected who came from the Dutch fishing village Volendam. Due to historical reasons, the village became isolated and remained so over centuries; the inhabitants began to marry close relatives. This resulted in a conspicuously high amount of cases of the illness in this village, as PCH usually only occurs, when both parents pass on the predisposition for this disease.
Families from Volendam were the starting point for the present study.
In the mean time, cases of the disease have been discovered in other parts of Europe. Based on these, scientists have been able to prove that the majority of the cases of PCH2, including those of the village of Volendam, have a common ancestor. This common ancestor lived during the 17th century. The results of the most recent research will be published in the renowned magazine Nature Genetics.
“The identification of mutations, which cause PCH2 and PCH4, is an important step in the research of ponto cerebellar hypoplasia,” according to Dr. Budde.