Limb disorders

Gene: RSG1

Green List (high evidence)

Comment on list classification: There are 2 unrelated individuals reported in literature with biallelic RSG1 and polydactyly. Knockout Rsg1-/- mice showed polydactyly and early lethality. Hence, this gene should be promoted to Green at the next update. Inclusion on this panel also ensures inclusion on R27 Paediatric disorders panel.

Created: 10 Apr 2026, 3:01 p.m. | Last Modified: 10 Apr 2026, 3:01 p.m.

Panel Version: 7.27

PMID 40593758 Vazquez et al., 2025
Three individuals from unrelated families reported with biallelic RSG1 variants: c.226G>C (p.Ala76Pro); c.G353A (p.Gly118Glu); c.562C>T (p.Arg188Trp).
Case 1) Polyhydramnios, bilateral pre-and post-axial polydactyly on hands and feet, hypertelorism, high arched palate.
Case 2) aortic coarctation cardiac septal defect and post-axial polydactyly in one hand and pre-axial polydactyly on both feet.
Case 3) hypoplastic and cystic dysplastic kidneys, oligohydramnios, microcephaly, and IUGR.

Functional evidence:
PMID: 29038301 Agbu et al., 2018 - Rsg1 is essential for ciliogenesis in mice. The Rsg1-/- mice showed completely penetrant polydactyly on all limbs and lethality at embryonic day 12.5. Rsg1 mutant embryos have fewer primary cilia than wild-type embryos.
Sources: Literature

Created: 10 Apr 2026, 2:59 p.m.

Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal

Phenotypes
ciliopathy, MONDO:0005308; polydactyly, MONDO:0021003

Publications

• 29038301
• 40593758