Which feature is characteristic of Trisomy 13/Patau Syndrome?

Trisomy 13, also known as Patau syndrome, is associated with several distinctive physical features and congenital anomalies. One characteristic feature of Patau syndrome is microcephaly, or a smaller than average head size, which can be what the option of "small head" refers to in this context. Individuals with this syndrome typically exhibit a variety of other structural anomalies; however, the presence of a small head is consistent with the neurodevelopmental issues and growth retardation often observed in affected infants.

Other features associated with Patau syndrome may include facial clefts, polydactyly, and severe intellectual disability. While sparse hair, short neck, and macroglossia (enlarged tongue) can occur in different genetic conditions or syndromes, they are not hallmark features specifically associated with Trisomy 13. Focusing on the head size aligns closely with the clinical presentation commonly seen in these affected individuals, underscoring the significance of head size as a notable aspect of this syndrome.