Ehlers-Danlos Syndrome, Classic Type - Diagnostic Tests

Diagnostic Tests

Examination of full thickness skin biopsy by transmission electron microscopy: disturbed collagen fibrillogenesis, cauliflower deformities of collagen fibrils

Molecular analysis:

  • COL5A1 “null” allele testing: to evaluate whether both COL5A1 alleles have stable transcipts
  • mutation analysis: mutations on one allele of genes coding for collagen type V (COL5A1, COL5A2)

Diagnostic Tools

This section offers to professional users instruments helpful to establish the disease diagnosis. Specific entries include:

  1. model questionnaires, protocols, or checklists, which may guide clinicians and laboratory personnel in the diagnostic procedure of specific disease groups/subgroups;
  2. a list of cell biology/biochemical tools used for laboratory diagnosis of specific diseases or group of diseases;
  3. a list of molecular genetics tools, including mutational screening procedures, oligonucleotide primer sequences, PCR amplification conditions, and other details for selected diseases. In this section, you also find the link for the gene-specific page of the Weizmann Institute of Science GeneCards website ( which is an integrated database including information on disease relationships, SNPs, gene expression, gene function and more.
  4. a mutation database with a GENESKIN updated list of the mutations identified in the genes responsible for selected diseases. A link with the gene-specific page at the Human Gene Mutation Database maintained at the University of Wales in Cardiff ( and other databases, such as the collagen database in Leicester (, is also available.

Model Questionnaire

Here you will find the downloadable version of the Ehlers-Danlos syndrome, classic type patient form. This document is currently used to collect patient details before sending the biological sample to the diagnostic laboratory, in order to ease cellular and/or molecular investigations.

Clinical checklist (downloadable version)

Cell Biology Tools

This information can be made available on request. Please send your request to Prof. Paul Coucke (

Molecular Genetic Tools

Causative genes

COL5A1 Genecards Logo
COL1A1 Genecards Logo

Screening procedure

COL5A1 "null" allele testing. Polymorphic markers in the expressed region of the genomic DNA may be used to determine if both COL5A1 alleles have stable transcripts. Initially, testing determines if the individual is heterozygous for one of several COL5A1 polymorphic exonic markers in genomic DNA. Then, COL5A1 cDNA is tested to determine if both alleles are present. If only one of the two COL5A1 alleles is present in cDNA, it is assumed that the absent allele is "null." COL5A1 "null" allele testing requires cultured fibroblasts, as it examines both genomic DNA and cDNA. It does not identify mutations within the COL5A1 gene.
For polymorphic markers used in this analysis we would like to refer to the following publication:

  • Malfait F, Coucke P, Symoens S, Loeys B, Nuytinck L, De Paepe A. 2005. The molecular basis of classic Ehlers-Danlos syndrome: a comprehensive study of biochemical and molecular findings in 48 unrelatedpatients. Hum Mutat (1):28-37.

Mutational screening

Mutational screening of COL5A1 and COL5A2 is usually performed by amplification of cDNA generated by RT-PCR using RNA extracted from a skin biopsy or cultured fibroblasts as template. Detected mutations are then confirmed on genomic DNA. Alternatively, mutational screening may be performed directly on genomic DNA.
For the primers used in the analysis of the COL5A1 and COL5A2 gene, we would like to refer to the following publications:

  • Emanuel BS, Cannizzaro LA, Seyer JM, Myers JC. 1985. Human alpha 1(III) and alpha 2(V) procollagen genes are located on the long arm of chromosome 2. Proc Natl Acad Sci U S A 82(10):3385-9.
  • Greenspan DS, Cheng W, Hoffman GG. 1991. The pro-alpha 1(V) collagen chain. Complete primary structure, distribution of expression, and comparison with the pro-alpha 1(XI) collagen chain. J Biol Chem 266(36):24727-33.
  • Takahara K, Hoffman GG, Greenspan DS. 1995. Complete structural organization of the human alpha 1 (V) collagen gene (COL5A1): divergence from the conserved organization of other characterized fibrillar collagen genes. Genomics. Oct 10;29(3):588-97.

Contact person: Paul Coucke, Supervisor Connective tissue lab

Mutation Database

Causative genes


For mutation lists, please refer to the following paper:

  • Malfait F, De Paepe A. 2005. Molecular genetics in classic Ehlers-Danlos syndrome. Am J Med Genet C Semin Med Genet 139(1):17-23. For further information, please contact Prof. Paul Coucke (