marshall–smith syndrome marshall–smith syndrome marshall-smith syndrome, discovered in 1971 (marshall, graham, scott, boner, & smith), is characterized by unusual accelerated skeletal maturation (usually starting before birth) and symptoms like conspicuous physical characteristics, respiratory difficulties, and mental retardation. cases described in the literature show a clinical variability regarding related symptoms. for instance, respiratory difficulties are ranging from absent to severe difficulties. marshall-smith syndromeother namesgreig's syndrome, polysyndactyly cephalopolysyndactyly syndrome, accelerated skeletal maturation, marshall-smith type, marshall–smith–weaver syndrome presentation the syndrome is a rare clinical disorder. physical overgrowth accelerated skeletal maturation dysmorphic facial features prominent eyes bluish sclerae coarse eyebrows upturned nose radiologic examination accelerated osseous maturation phalangeal abnormalities tubular thinning of the long bones skull abnormalities mental often associated with intellectual disability (of variable degree) genotype the first gene - nfix - that could cause the syndrome has been identified. this gene is located on the short arm of chromosome 19 (19p13.1). diagnosis clinical course respiratory difficulties (like upper airway obstruction. (note regarding clinical variability: respiratory difficulties might be absent.) pneumonia failure to thrive psychomotor retardation respiratory complications are often cause of death in early infancy. differential diagnosis marshall–smith syndrome is not to be confused with: marshall syndrome sotos (like) syndrome (malan syndrome) weaver-smith syndrome (wss) terminology translated english: marshall–smith syndrome español: síndrome de marshall–smith français: le syndrome de marshall–smith italiano: sindrome di marshall–smith nederlands: marshall–smithsyndroom, syndroom van marshall–smith polski: zespół marshalla–smitha, zespół marshalla i smitha русский: синдром маршалла–смита