{"type": "root", "children": [{"type": "p", "children": [{"type": "t", "text": "\n Growth differentiation factor 6 (GDF6) is a member of a distinct subgroup within the bone morphogenetic protein (BMP) family that plays a crucial role in the coordinated formation and patterning of the skeletal system as well as ocular development. In the developing skeleton, GDF6 is expressed in specific subsets of joint regions where it helps establish boundaries between different skeletal elements. Functional studies in mice have shown that loss of Gdf6 results in defects in joint, ligament, and cartilage formation—particularly affecting structures such as the wrist, ankle, middle ear, and cranial sutures—thereby underscoring its essential role in proper joint morphogenesis and vertebral patterning."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "1"}]}, {"type": "t", "text": ""}]}, {"type": "t", "text": "\n \n "}, {"type": "p", "children": [{"type": "t", "text": "\n In the context of eye development, mutations in GDF6 have been linked to a spectrum of ocular anomalies, including coloboma, microphthalmia, and even anophthalmia. Clinical and experimental evidence from both human genetic studies and animal models indicates that alterations in GDF6 expression disrupt the dorso‐ventral patterning of the retina and impair photoreceptor survival, leading to a variety of congenital eye malformations."}, {"type": "fg", "children": [{"type": "fg_fs", "start_ref": "3", "end_ref": "6"}]}, {"type": "t", "text": ""}]}, {"type": "t", "text": "\n \n "}, {"type": "p", "children": [{"type": "t", "text": "\n Risk alleles near the GDF6 gene have also been implicated in age‐related macular degeneration by altering its expression, which suggests that GDF6 may contribute to retinal vascular development and homeostasis."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "7"}]}, {"type": "t", "text": " In addition, detailed investigations of the regulatory landscape of the Gdf6 locus have delineated distinct cis‐regulatory elements that drive its tissue‐specific expression in developing joints, further emphasizing the importance of precise spatial and temporal regulation to its function."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "8"}]}, {"type": "t", "text": ""}]}, {"type": "t", "text": "\n \n "}, {"type": "p", "children": [{"type": "t", "text": "\n Finally, genome‐wide association studies and candidate gene analyses have identified GDF6 as a potential contributor to craniofacial anomalies such as nonsyndromic cleft lip with or without cleft palate, broadening its functional repertoire in craniofacial development."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "9"}]}, {"type": "t", "text": " Collectively, these findings establish GDF6 as a key modulator in both skeletal and ocular development, with mutations or dysregulation producing a range of developmental anomalies.\n "}]}, {"type": "rg", "children": [{"type": "r", "ref": 1, "children": [{"type": "t", "text": "Stephen H Settle, Ryan B Rountree, Abhishek Sinha, et al. 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