A composite figure illustrating the historical and genetic context of Down syndrome (Trisomy 21). Panel A shows a portrait of John Langdon Down, who first described the clinical features. Panel B is a black-and-white clinical photograph of two individuals; the male exhibits characteristic dysmorphic facial features of Down syndrome, including upslanting palpebral fissures, epicanthic folds, and a flattened nasal bridge. Panel C depicts Dr. Jérôme Lejeune, the geneticist who identified the chromosomal basis of the condition. Panel D shows a spectral karyotype (SKY) or multicolor fluorescence in situ hybridization (m-FISH) arrangement. All autosomal pairs are numbered 1 through 22, along with X and Y sex chromosomes. A pink arrow highlights the genetic hallmark of the disorder: three copies of chromosome 21 (Trisomy 21) instead of the typical homologous pair. This educational graphic links clinical phenotype with its underlying cytogenetic pathology, suitable for medical genetics and pediatrics curricula.

Clinical photograph of a 15-year-old female patient exhibiting phenotypic facial features characteristic of Down syndrome (Trisomy 21). The image demonstrates a flattened facial profile with a notably low-set and depressed nasal bridge. Ocular findings include upslanting palpebral fissures and prominent bilateral epicanthic folds (medial epicanthal skin folds) covering the inner canthi. Additional craniofacial features include a relatively small oral cavity and mild brachycephaly. The patient has light skin with fine freckling across the midface. This image serves as a teaching tool for medical genetics and clinical pediatrics, illustrating the classic dysmorphic facial features associated with Trisomy 21 in an adolescent. The clinical context suggests an association with Morning Glory Syndrome (MGS), though the internal ocular pathologies are not visible in this external facial view.

This composite clinical photograph displays the postnatal morphological features of a fetus with trisomy 21 (Down syndrome). Panel A provides a facial profile view illustrating several classic dysmorphic features, including a flat facial profile, telecanthus/hypertelorism (widely spaced eyes), a markedly depressed nasal bridge, and macroglossia resulting in a protruding tongue. Panel B shows the right hand of the fetus being examined with surgical forceps, highlighting a single transverse palmar crease (simian crease), a common soft marker associated with various chromosomal abnormalities. The images are set against a blue background with a metric ruler for scale, typical of a clinical pathology or autopsy setting. These findings serve as physical manifestations of the underlying genetic duplication of 21q22.12-q22.3, which includes critical regions associated with the Down syndrome phenotype.

Clinical photograph of a pediatric patient exhibiting characteristic dysmorphic facial features and ophthalmologic abnormalities associated with Down syndrome (Trisomy 21). The image primarily demonstrates bilateral congenital ectropion of the upper eyelids, characterized by an outward eversion of the lid margins and exposure of the palpebral conjunctiva. Other visible craniofacial findings include bilateral epicanthal folds (skin folds covering the medial canthus), a flattened nasal bridge, and midface hypoplasia. There is also evident periorbital edema and an upward slanting of the palpebral fissures. This visual case illustrates the rare manifestation of congenital upper lid ectropion in the context of anterior lamellar shortening and general horizontal lid laxity. The photograph is essential for teaching neonatal and pediatric ophthalmology diagnostic signs and the phenotypic spectrum of Trisomy 21.