J Pediatr Genet 2022; 11(02): 144-146
DOI: 10.1055/s-0040-1715640
Case Report

A Truncating Variant of CHRNG as a Cause of Escobar Syndrome: A Multiple Pterygium Syndrome Subtype

1   Department of Pediatrics, University of Arizona College of Medicine, Tucson, Arizona, United States
2   Section of Neurology and Developmental Neurosciences, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, United States
Shalinkumar Patel
1   Department of Pediatrics, University of Arizona College of Medicine, Tucson, Arizona, United States
Mohammad Y. Bader
1   Department of Pediatrics, University of Arizona College of Medicine, Tucson, Arizona, United States
1   Department of Pediatrics, University of Arizona College of Medicine, Tucson, Arizona, United States
› Author Affiliations
Funding None.


Escobar syndrome is a milder variant of multiple pterygium syndrome characterized by pterygia, scoliosis, and multiple congenital contractures. It is most frequently due to a genetic variant in CHRNG, which encodes the γ-subunit of the nicotinic acetylcholine receptor. Though the subunit is considered a “fetal” form and transitions to the “adult” ε-subunit by 33 weeks' gestation, the pathogenic musculoskeletal effects during fetal development render children with this condition permanently affected. We report a neonate with homozygous CHRNG c.117dupC and discuss some of the downstream clinical effects we observed with this variant.

Ethical Approval

Parental permission was obtained for publication.

Supplementary Material

Publication History

Received: 18 March 2020

Accepted: 15 July 2020

Article published online:
26 August 2020

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