Investigators in Sao Paulo, Brazil, report a female infant born at term to healthy consanguineous parents who was examined at 9 months for delayed development. She showed hepatosplenomegaly, and widespread Mongolian spots extending over the back and upper and lower extremities. Funduscopic examination revealed cherry red spot of the retina, consistent with a diagnosis of the lysosomal disease, GM1 gangliosidosis type 1. 
COMMENT. The Mongolian spots result from entrapment of melanocytes in the dermis because of arrested transdermal migration from the neural crest into the epidermis. Hurler syndrome and GM1 gangliosidosis type 1 are diseases associated with generalized Mongolian spots. Infants with GM1 gangliosidosis type 1, also known as Pseudo-Hurler’s disease, show facial abnormalities that include frontal bossing, depressed nasal bridge, macroglossia, large low-set ears, and marked hirsutism. About 50% have cherry-red spots. The association of Mongolian spots with the lysosomal disease GM1 gangliosidosis type 1 was not recorded in older neurology textbooks, but a PubMed search found 10 references in the last 30 years [2, 3]. Mongolian spots when unusually numerous should prompt an examination for the lysosomal disease, GM1 gangliosidosis type 1.