S-adenosylhomocysteine hydrolase (AHCY) deficiency is a rare autosomal recessive disorder in methionine metabolism caused by mutations in the AHCY gene. Main characteristics are psychomotor delay including delayed myelination and myopathy (hypotonia, absent tendon reflexes etc.) from birth, mostly associated with hypermethioninaemia, elevated serum creatine kinase levels and increased genome wide DNA methylation. The prime function of AHCY is to hydrolyse and efficiently remove S-adenosylhomocysteine, the by-product of transmethylation reactions and one of the most potent methyltransferase inhibitors. In this study, we set out to more specifically characterize DNA methylation changes in blood samples from patients with AHCY deficiency. Global DNA methylation was increased in two of three analysed patients. In addition, we analysed the DNA methylation levels at differentially methylated regions (DMRs) of six imprinted genes (MEST, SNRPN, LIT1, H19, GTL2 and PEG3) as well as Alu and LINE1 repetitive elements in seven patients. Three patients showed a hypermethylation in up to five imprinted gene DMRs. Abnormal methylation in Alu and LINE1 repetitive elements was not observed. We conclude that DNA hypermethylation seems to be a frequent but not a constant feature associated with AHCY deficiency that affects different genomic regions to different degrees. Thus AHCY deficiency may represent an ideal model disease for studying the molecular origins and biological consequences of DNA hypermethylation due to impaired cellular methylation status.

The aim of this paper is to show how the German artistic ballad reflects the question of the social role of art and the artist in the second half of the 20th century, when – parallel with the affirmation of the concept of socially engaged and conscious art – the question of the status of an intellectual in society becomes very important. Within this study of German ballad, this literary and musical genre is understood as a short discursive form that deals with existential questions and stoned truths and values by means of apparently naive and simple presented events, offering in that way an opportunity for critical reflection in the act of reception. Two representative ballads are interpreted within this paper: Adorno's tongue (Adornos Zunge, 1965) from Gunter Grass and Ballad to the Poet Francois Villon (Ballade auf den Dichter Francois Villon, 1968) from Wolf Biermann. The immanent text interpretation of the two selected ballads shows the way in which literature, as an aesthetic response to reality, can offer the relevant critical perception of society, considering the historical moment of origin of the text as well as the philosophical and existential views of the author. DOI: 10.5901/mjss.2014.v5n13p257