What is common among disorders related to FGFR2?

Midface retrusion is a common characteristic observed in disorders associated with FGFR2 (Fibroblast Growth Factor Receptor 2), such as Crouzon syndrome and Apert syndrome. FGFR2 plays a crucial role in cranial development, and mutations in this gene can lead to craniosynostosis, where the sutures of the skull fuse prematurely. This has a direct impact on the shape of the skull and facial features, often resulting in midface hypoplasia or retrusion.

Conditions linked to FGFR2 mutations typically manifest in craniofacial abnormalities alongside potential limb or digit anomalies, although midface retrusion remains a hallmark feature. The other choices do not prominently feature in this context: absent limbs is typically associated with different genetic pathways, aplasia of middle phalanges is more often related to limb malformations not specifically tied to FGFR2, and preaxial polydactyly is associated with the SHH pathway rather than FGFR2. Thus, midface retrusion stands out as the characteristic feature most commonly recognized in FGFR2-related disorders.