Background: Greenberg dysplasia is a rare, autosomal recessive, prenatal lethal bone dysplasia caused by biallelic pathogenic variants in the lamin B receptor (LBR) gene. Pathogenic variants in LBR are also associated with Pelger-Huët anomaly, an autosomal dominant benign abnormality of the nuclear shape and chromatin organization of blood granulocytes, and Pelger-Huët anomaly with variable skeletal anomalies, a mild, regressing to moderate-severe autosomal recessive condition. Conditions with abnormal sterol metabolism and different genetic basis have clinical and radiographic features similar to Greenberg dysplasia, for example X-linked dominant chondrodysplasia punctata, Conradi-Hünermann type, and CHILD syndrome, and other conditions with unknown genetic etiology display very similar features, for example, dappled diaphyseal dysplasia and Astley-Kendall dysplasia.
Methods: We present a fetus with typical clinical and radiographic features of Greenberg dysplasia, and review the literature.
Results: Genetic testing confirmed the diagnosis Greenberg dysplasia: homozygosity for a pathogenic variant in LBR.
Conclusion: Comparing the clinical and radiographic phenotypes of Greenberg dysplasia, dappled diaphyseal dysplasia, and Astley-Kendall dysplasia, we suggest that these are allelic disorders.
Keywords: Greenberg dysplasia; LBR; Skeletal dysplasia; abnormal sterol metabolism.
© 2020 The Authors. Molecular Genetics & Genomic Medicine published by Wiley Periodicals, Inc.