Spondyloperipheral dysplasia as the mosaic form of platyspondylic lethal skeletal dyplasia torrance type in mother and fetus with the same COL2A1 mutation

Abstract

We describe a fetus with platyspondylic lethal skeletal dysplasia, Torrance type (PLSD-T), a rare skeletal dysplasia characterized by platyspondyly, extremely short limbs, and mild brachydactyly. Mutation analysis of COL2A1 identified a novel in-frame deletion c.4458_4460delCTT (p.Phe1486del) in the C-propeptide region of the molecule, confirming the clinical diagnosis. The phenotype in the mother was compatible with mild spondyloperipheral dysplasia (SPPD). Molecular studies documented somatic mosaicism for the same mutation in the mother. This observation further highlights the causal relationship between PLSD-T and SPPD and emphasizes the importance of evaluating parents when confronted with a skeletal dysplasia in a prenatal setting.