Spondylometaphyseal / Spondyloepi-(meta)-physeal Dysplasia Panel

Last modified: Mar 21, 2018


  • Is a 28 gene panel that includes assessment of non-coding variants
  • Is ideal for patients with a clinical suspicion of spondylometaphyseal dysplasia or spondyloepi-(meta)-physeal dysplasia. The genes on this panel are included in the Comprehensive Growth Disorders / Skeletal Dysplasias and Disorders Panel.

Analysis methods

  • PLUS
  • SEQ


3-4 weeks

Number of genes


Test code


CPT codes

SEQ 81408
DEL/DUP 81479
SEQ 81479


The Blueprint Genetics Spondylometaphyseal / Spondyloepi-(meta)-physeal Dysplasia Panel (test code MA1701):

  • Is a 28 gene panel that includes assessment of selected non-coding disease-causing variants
  • Is available as PLUS analysis (sequencing analysis and deletion/duplication analysis), sequencing analysis only or deletion/duplication analysis only

ICD codes

Commonly used ICD-10 code(s) when ordering the Spondylometaphyseal / Spondyloepi-(meta)-physeal Dysplasia Panel

ICD-10 Disease
Q77.8 Spondylometaphyseal or Spondyloepi-(meta)-physeal dysplasia

Sample Requirements

  • EDTA blood, min. 1 ml
  • Purified DNA, min. 3μg
  • Saliva (Oragene DNA OG-500 kit)

Label the sample tube with your patient’s name, date of birth and the date of sample collection.

Note that we do not accept DNA samples isolated from formalin-fixed paraffin-embedded (FFPE) tissue.

The spondylometaphyseal dysplasias constitute a very complex heterogeneous group of disorders. The disorders are characterized by the association of spondular dysplasia and metaphyseal abnormalities of the tubular bones and are associated with walking and growth disturbances that become evident in early childhood. The disorders involve platyspondyly (flattened vertebrae) and marked hip and knee metaphyseal lesions. The different forms of spondylometaphyseal dysplasia are distinguished by the localization and severity of involvement of the affected metaphyses. In addition to the Kozlowski type, which is the most common form, three subgroups can be distinguished by the appearance of the femoral neck. In the first group the changes are severe with absent ossification of the femoral neck and coxa vara. In the second group the changes of the femoral neck are moderate and in the third mild metaphyseal irregularities are only visible. Spondylometaphyseal dysplasia may also occur in association with other clinical manifestations such as facial dysmorphism and dentinogenesis imperfecta. The Kozlowski type of spondylometaphyseal dysplasia results in severe kyphoscoliosis and is caused by mutations in the TRPV4 gene. It is transmitted in an autosomal dominant manner, as well as the form of spondylometaphyseal dysplasia (‘corner fracture’ or Sutcliffe type), the Algerian (or Schmidt) type and some moderate forms. Several autosomal recessive forms have also been identified, including type A4 and an axial type associated with retinitis pigmentosa and optic atrophy. A form of spondylometaphyseal dysplasia with X-linked transmission has also been reported.

Genes in the Spondylometaphyseal / Spondyloepi-(meta)-physeal Dysplasia Panel and their clinical significance

Gene Associated phenotypes Inheritance ClinVar HGMD
ACAN# Spondyloepimetaphyseal dysplasia, aggrecan type, Spondyloepiphyseal dysplasia, Kimberley type, Osteochondritis dissecans, short stature, and early-onset osteoarthritis AD/AR 14 30
ACP5 Spondyloenchondrodysplasia with immune dysregulation AR 10 26
B3GALT6 Spondyloepimetaphyseal dysplasia with joint laxity, Ehlers-Danlos syndrome AR 15 25
BGN Spondyloepimetaphyseal dysplasia, X-linked 8 7
CANT1 Desbuquois dysplasia AR 18 27
CHST3 Spondyloepiphyseal dysplasia with congenital joint dislocations (recessive Larsen syndrome) AR 15 36
COL2A1 Avascular necrosis of femoral head, Rhegmatogenous retinal detachment, Epiphyseal dysplasia, with myopia and deafness, Czech dysplasia, Achondrogenesis type 2, Platyspondylic dysplasia Torrance type, Hypochondrogenesis, Spondyloepiphyseal dysplasia congenital (SEDC), Spondyloepimetaphyseal dysplasia (SEMD) Strudwick type, Kniest dysplasia, Spondyloperipheral dysplasia, Mild SED with premature onset arthrosis, SED with metatarsal shortening, Stickler syndrome type 1 AD 138 541
COL11A1 Marshall syndrome, Fibrochondrogenesis, Stickler syndrome type 2 AD/AR 22 81
COL11A2 Weissenbacher-Zweymuller syndrome, Deafness, Otospondylomegaepiphyseal dysplasia, Fibrochondrogenesis, Stickler syndrome type 3 (non-ocular) AD/AR 23 54
DDR2 Spondylometaepiphyseal dysplasia, short limb-hand type AR 11 7
DYM Dyggve-Melchior-Clausen dysplasia, Smith-McCort dysplasia AR 20 34
EIF2AK3 SED, Wolcott-Rallison type AR 9 73
HSPG2 Schwartz-Jampel syndrome, Dyssegmental dysplasia Silverman-Handmaker type, Dyssegmental dysplasia Rolland-Desbuquis type AD/AR 15 53
INPPL1 Opsismodysplasia AR 16 29
KIF22 Spondyloepimetaphyseal dysplasia with joint laxity, type 2 AD 4 4
LONP1 Cerebral, Ocular, Dental, Auricular, and Skeletal anomalies (CODAS) syndrome AR 6 16
MATN3 Spondyloepimetaphyseal dysplasia Matrilin type, Multiple epiphyseal dysplasia type 5 (EDM5) AD/AR 8 24
MMP13 Metaphyseal anadysplasia 1, Metaphyseal dysplasia, Spahr type, Spondyloepimetaphyseal dysplasia, Missouri type AD/AR 7 6
NKX3-2 Spondylo-megaepiphyseal-metaphyseal dysplasia AR 3 4
PAPSS2 Brachyolmia 4 with mild epiphyseal and metaphyseal changes, SEMD PAPPS2 type AR 10 19
PCYT1A Spondylometaphyseal dysplasia with cone-rod dystrophy AR 11 20
RAB33B Dyggve-Melchior-Clausen syndrome, Smith-McCort dysplasia 2 AR 6 6
RMRP Cartilage-hair hypoplasia, Metaphyseal dysplasia without hypotrichosis, Anauxetic dysplasia AR 29 123
SLC39A13 Spondylodysplastic Ehlers-Danlos syndrome AR 2 8
SMARCAL1 Schimke immunoosseous dysplasia AR 12 75
TRAPPC2* Spondyloepiphyseal dysplasia tarda XL 12 54
TRPV4 Metatropic dysplasia, Spondyloepiphyseal dysplasia Maroteaux type, Parastremmatic dwarfism, Hereditary motor and sensory neuropathy, Spondylometaphyseal dysplasia Kozlowski type, Spinal muscular atrophy, Charcot-Marie-Tooth disease, Brachyolmia (autosomal dominant type), Familial Digital arthropathy with brachydactyly AD 58 74
WISP3 Arthropathy, progressive pseudorheumatoid, of childhood, Spondyloepiphyseal dysplasia tarda with progressive arthropathy AR 13 69

* Some, or all, of the gene is duplicated in the genome. Read more.

# The gene has suboptimal coverage (means <90% of the gene’s target nucleotides are covered at >20x with mapping quality score (MQ>20) reads).

The sensitivity to detect variants may be limited in genes marked with an asterisk (*) or number sign (#)

Gene refers to the HGNC approved gene symbol; Inheritance refers to inheritance patterns such as autosomal dominant (AD), autosomal recessive (AR), X-linked (XL), X-linked dominant (XLD) and X-linked recessive (XLR); ClinVar refers to the number of variants in the gene classified as pathogenic or likely pathogenic in this database (ClinVar); HGMD refers to the number of variants with possible disease association in the gene listed in Human Gene Mutation Database (HGMD). The list of associated, gene specific phenotypes are generated from CGD or Orphanet databases.

Non-coding variants covered by the panel

Gene Genomic location HG19 HGVS RefSeq RS-number
CANT1 Chr17:77005745 c.-342+1G>A NM_138793.3
COL11A1 Chr1:103488576 c.1027-24A>G NM_080629.2
COL11A1 Chr1:103386637 c.3744+437T>G NM_080629.2
COL11A1 Chr1:103491958 c.781-450T>G NM_080629.2 rs587782990
COL2A1 Chr12:48379984 c.1527+135G>A NM_001844.4
HSPG2 Chr1:22211006 c.1654+15G>A NM_005529.5
HSPG2 Chr1:22215993 c.574+481C>T NM_005529.5
RMRP Chr9:35657745 NR_003051.3 rs377349293
RMRP Chr9:35657746 NR_003051.3 rs551655682
WISP3 Chr6:112381431 c.103-763G>T NM_198239.1
WISP3 Chr6:112386227 c.643+27C>G NM_198239.1 rs200472841

Added and removed genes from the panel

Genes added Genes removed

Test strength

The strengths of this test include:
  • CAP and ISO-15189 accreditations covering all operations at Blueprint Genetics including all Whole Exome Sequencing, NGS panels and confirmatory testing
  • CLIA-certified personnel performing clinical testing in a CLIA-certified laboratory
  • Powerful sequencing technologies, advanced target enrichment methods and precision bioinformatics pipelines ensure superior analytical performance
  • Careful construction of clinically effective and scientifically justified gene panels
  • Our Nucleus online portal providing transparent and easy access to quality and performance data at the patient level
  • Our publically available analytic validation demonstrating complete details of test performance
  • 1479 non-coding disease causing variants in Blueprint WES assay (please see below ‘Non-coding disease causing variants covered by this panel’)
  • Our rigorous variant classification based on modified ACMG variant classification scheme
  • Our systematic clinical interpretation workflow using proprietary software enabling accurate and traceable processing of NGS data
  • Our comprehensive clinical statements

Test limitations

Genes with suboptimal coverage in our assay are marked with number sign (#) and genes with partial, or whole gene, segmental duplications in the human genome are marked with an asterisk (*) if they overlap with the UCSC pseudogene regions. Gene is considered to have suboptimal coverage when >90% of the gene's target nucleotides are not covered at >20x with mapping quality score (MQ>20) reads. The technology may have limited sensitivity to detect variants in genes marked with these symbols (please see the Panel content table above).

This test does not detect the following:
  • Complex inversions
  • Gene conversions
  • Balanced translocations
  • Mitochondrial DNA variants
  • Repeat expansion disorders unless specifically mentioned
  • Non-coding variants deeper than ±20 base pairs from exon-intron boundary unless otherwise indicated (please see above Panel Content / non-coding variants covered by the panel).

This test may not reliably detect the following:

  • Low level mosaicism
  • Stretches of mononucleotide repeats
  • Indels larger than 50bp
  • Single exon deletions or duplications
  • Variants within pseudogene regions/duplicated segments

The sensitivity of this test may be reduced if DNA is extracted by a laboratory other than Blueprint Genetics.

For additional information, please refer to the Test performance section and see our Analytic Validation.

The Blueprint Genetics spondylometaphyseal / spondyloepi-(meta)-physeal dysplasia panel covers classical genes associated with spondylometaphyseal or Spondyloepi-(meta)-physeal dysplasia. The genes on the panel have been carefully selected based on scientific literature, mutation databases and our experience.

Our panels are sliced from our high-quality whole exome sequencing data. Please see our sequencing and detection performance table for different types of alterations at the whole exome level (Table).

Assays have been validated for different starting materials including EDTA-blood, isolated DNA (no FFPE), saliva and dry blood spots (filter card) and all provide high-quality results. The diagnostic yield varies substantially depending on the assay used, referring healthcare professional, hospital and country. Blueprint Genetics' Plus Analysis (Seq+Del/Dup) maximizes the chance to find a molecular genetic diagnosis for your patient although Sequence Analysis or Del/Dup Analysis may be a cost-effective first line test if your patient's phenotype is suggestive of a specific mutation type.

Performance of Blueprint Genetics Whole Exome Sequencing (WES) assay. All individual panels are sliced from WES data.

Sensitivity % (TP/(TP+FN) Specificity %
Single nucleotide variants 99.65% (412,456/413,893) >99.99%
Insertions, deletions and indels by sequence analysis
1-10 bps 96.94% (17,070/17,608) >99.99%
11-50 bps 99.07% (957/966) >99.99%
Copy number variants (exon level dels/dups)
Clinical samples (small CNVs, n=52)
1 exon level deletion 92.3% (24/26) NA
2 exons level deletion/duplication 100.0% (11/11) NA
3-7 exons level deletion/duplication 93.3% (14/15) NA
Microdeletion/-duplication sdrs (large CNVs, n=37))
Size range (0.1-47 Mb) 100% (37/37)
Simulated CNV detection
2 exons level deletion/duplication 90.98% (7,357/8,086) 99.96%
5 exons level deletion/duplication 98.63% (7,975/8,086) 99.98%
The performance presented above reached by WES with the following coverage metrics
Mean sequencing depth at exome level 174x
Nucleotides with >20x sequencing coverage (%) 99.4%


The target region for each gene includes coding exons and ±20 base pairs from the exon-intron boundary. In addition, the panel includes non-coding variants if listed above (Non-coding variants covered by the panel). Some regions of the gene(s) may be removed from the panel if specifically mentioned in the ‘Test limitations” section above. The sequencing data generated in our laboratory is analyzed with our proprietary data analysis and annotation pipeline, integrating state-of-the art algorithms and industry-standard software solutions. Incorporation of rigorous quality control steps throughout the workflow of the pipeline ensures the consistency, validity and accuracy of results. Our pipeline is streamlined to maximize sensitivity without sacrificing specificity. We have incorporated a number of reference population databases and mutation databases such as, but not limited, to 1000 Genomes Project, gnomAD, ClinVar and HGMD into our clinical interpretation software to make the process effective and efficient. For missense variants, in silico variant prediction tools such as SIFT, PolyPhen, MutationTaster are used to assist with variant classification. Through our online ordering and statement reporting system, Nucleus, the customer has an access to details of the analysis, including patient specific sequencing metrics, a gene level coverage plot and a list of regions with inadequate coverage if present. This reflects our mission to build fully transparent diagnostics where customers have easy access to crucial details of the analysis process.

Clinical interpretation

We provide customers with the most comprehensive clinical report available on the market. Clinical interpretation requires a fundamental understanding of clinical genetics and genetic principles. At Blueprint Genetics, our PhD molecular geneticists, medical geneticists and clinical consultants prepare the clinical statement together by evaluating the identified variants in the context of the phenotypic information provided in the requisition form. Our goal is to provide clinically meaningful statements that are understandable for all medical professionals regardless of whether they have formal training in genetics.

Variant classification is the corner stone of clinical interpretation and resulting patient management decisions. Our classifications follow the Blueprint Genetics Variant Classification Schemes based on the ACMG guideline 2015. Minor modifications were made to increase reproducibility of the variant classification and improve the clinical validity of the report. Our experience with tens of thousands of clinical cases analyzed at our laboratory allowed us to further develop the industry standard.

The final step in the analysis of sequence variants is confirmation of variants classified as pathogenic or likely pathogenic using bi-directional Sanger sequencing. Variant(s) fulfilling all of the following criteria are not Sanger confirmed: 1) the variant quality score is above the internal threshold for a true positive call, 2) an unambiguous IGV in-line with the variant call and 3) previous Sanger confirmation of the same variant at least three times at Blueprint Genetics. Reported variants of uncertain significance are confirmed with bi-directional Sanger sequencing only if the quality score is below our internally defined quality score for true positive call. Reported copy number variations with a size <10 exons are confirmed by orthogonal methods such as qPCR if the specific CNV has been seen less than three times at Blueprint Genetics.

Our clinical statement includes tables for sequencing and copy number variants that include basic variant information (genomic coordinates, HGVS nomenclature, zygosity, allele frequencies, in silico predictions, OMIM phenotypes and classification of the variant). In addition, the statement includes detailed descriptions of the variant, gene and phenotype(s) including the role of the specific gene in human disease, the mutation profile, information about the gene’s variation in population cohorts and detailed information about related phenotypes. We also provide links to the references used, congress abstracts and mutation databases to help our customers further evaluate the reported findings if desired. The conclusion summarizes all of the existing information and provides our rationale for the classification of the variant.

Identification of pathogenic or likely pathogenic variants in dominant disorders or their combinations in different alleles in recessive disorders are considered molecular confirmation of the clinical diagnosis. In these cases, family member testing can be used for risk stratification within the family. In the case of variants of uncertain significance (VUS), we do not recommend family member risk stratification based on the VUS result. Furthermore, in the case of VUS, we do not recommend the use of genetic information in patient management or genetic counseling. For eligible cases, Blueprint Genetics offers a no charge service to investigate the role of reported VUS (VUS Clarification Service).

Our interpretation team analyzes millions of variants from thousands of individuals with rare diseases. Thus, our database, and our understanding of variants and related phenotypes, is growing by leaps and bounds. Our laboratory is therefore well positioned to re-classify previously reported variants as new information becomes available. If a variant previously reported by Blueprint Genetics is re-classified, our laboratory will issue a follow-up statement to the original ordering health care provider at no additional cost.