A syndrome caused by large deletions of the telomereic end of the short arm of CHROMOSOME 4 (4p) in Wolf-Hirchhorn syndrome critial regions (WHSCRs). Several candidate genes have been identified including WHSC1 and WHSCH2 which appear to be responsible for the core phenotype and in combination with other linked and unlinked genes determine the severity and inclusion of rarer phenotypes. Most cases have a characteristic cranio-facial defect often referred to as "Greek helmet face" - a combined result of microcephaly, broad forehead, prominent glabella, hypertelorism, high arched eyebrows, short philtrum and micrognathia. In addition there is mental retardation, growth delays, epilepsy, and frequently a wide range of midline and skeletal defects, including hypospadias; CONGENITAL heart DEFECTS; cleft lip; cleft palate; colobomata; clubfoot; clinodactyly; scoliosis; and kyphosis.