Schinzel–Giedion syndrome  Schinzel–Giedion syndrome (SGS) is a congenital neurodegenerative terminal syndrome. It was first described in 1978 by Albert Schinzel (1944–) and Andreas Giedion (1925–) as a syndrome with severe midface retraction, skull anomalies, renal anomalies (hydronephrosis) and other anomalies. Babies born with Schinzel–Giedion syndrome have severe mental retardation, growth retardation (unless fed through a feeding tube) and global developmental delay.