Skeletal dysplasia

Gene: HSPG2

Green List (high evidence)

PMID: 38424183
- Biallelic pathogenic variants identified in five patients with Dyssegmental dysplasia, nonlethal Rolland-Desbuquois type. Haplotype analysis revealed a founder haplotype, two patients were homozygous for p.G3324R, and three patients were compound heterozygous for p.G3324R.

Created: 7 Mar 2024, 12:42 a.m. | Last Modified: 7 Mar 2024, 12:42 a.m.

Panel Version: 0.271

Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal

Phenotypes
Dyssegmental dysplasia, Rolland-Desbuquois type (MONDO:0009139)

Publications

• PMID: 38424183

Green List (high evidence)

Allelic disorders with some phenotypic overlap.

Schwartz-Jampel syndrome (SJS) is a rare autosomal recessive condition defined by the association of myotonia with chondrodysplasia; blepharophimosis is a key feature. More than 20 families reported.

Silverman-Handmaker dyssegmental dysplasia (DDSH) is a lethal autosomal recessive skeletal dysplasia with anisospondyly and micromelia. Individuals with DDSH also have a flat face, micrognathia, cleft palate and reduced joint mobility, and frequently have an encephalocele. The endochondral growth plate is short, the calcospherites (spherical calcium-phosphorus crystals produced by hypertrophic chondrocytes) are unfused, and there is mucoid degeneration of the resting cartilage. Two families reported. Appears associated with null variants.

Created: 5 Jun 2021, 4:43 a.m. | Last Modified: 26 Apr 2022, 1:57 a.m.

Panel Version: 0.13289

Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal

Phenotypes
Schwartz-Jampel syndrome, type 1, MIM# 255800; MONDO:0009717; Dyssegmental dysplasia, Silverman-Handmaker type, MIM# 224410; MONDO:0009140

Publications

• 11101850
• 16927315
• 11279527

Green List (high evidence)

Almost all reports are for SJS, with a single 2001 paper describing patients with DDSH. No clear genotype – phenotype correlation (OMIM).

LOF established

Created: 7 Feb 2020, 4:19 a.m. | Last Modified: 7 Feb 2020, 4:19 a.m.

Panel Version: 0.1278

Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal

Phenotypes
Dyssegmental dysplasia, Silverman-Handmaker type; Schwartz-Jampel syndrome, type 1

Publications

• PMID: 16927315