Introduction: Biallelic variants in the SCL35D1 gene have been originally associated with a severe skeletal dysplasia called “Schneckenbecken dysplasia” because of the resemblance of the pelvic shape to a snail. More recently, SLC35D1 variants have been associated with much milder phenotypes of skeletal dysplasia. Our report describes one such individual with a novel SLC35D1 variant. Case Presentation: A 17-year-old male with a coarse face and short stature was referred to our clinic. On his radiographic imaging, shortness of the long bones and metaphyseal flaring were detected. Using a clinical exome panel, we discovered a novel homozygous missense variant in the SLC35D1 gene, c.899G>T (p.Gly300Val). Conclusions: We identified a biallelic variant that was causative for a mild skeletal dysplasia and showed its phenotypic effects. Our observation confirms the existence of nonlethal skeletal dysplasias associated with biallelic SLC35D1 variants and suggests the existence of a phenotypic spectrum.

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