Ichthyosis NGS panel

Genes
(full
coding region):		 ABCA12, ABHD5, ALDH3A2, ALOX12B, ALOXE3, AP1S1, ATP2A2, ATP2C1, CARD14, CASP14, CDSN, CERS3, CLDN1, CYP4F22, EBP, ELOVL4, ERCC2, ERCC3, FLG, GJB2, GJB3, GJB4, GJB6, GTF2H5, KRT1, KRT2, KRT9, KRT10, LIPN, LORICRIN, MBTPS2, MPLKIP, NIPAL4, NSDHL, PEX7, PHYH, PNPLA1, POMP, SDR9C7, SLC27A4, SNAP29, SPINK5, ST14, STS, SUMF1, TGM1, TGM5

List of diseases covered by the panel
Lab method: NGS panel with CNV analysis
TAT: 6-9 weeks
Specimen requirements: 2-4 ml of blood with anticoagulant EDTA

1 µg DNA in TE, AE or pure sterile water at 100-250 ng/µl
The A260/A280 ratio should be 1.8-2.0. DNA sample should be run on an agarose gel as a single band, showing no degradation, alongside with a quantitative DNA marker.
Ordering information: Go to online ordering or download sample submission form

Indications for genetic testing:
1. Confirmation of clinical diagnosis
2. Differential diagnosis of nonsyndromic ichthyoses forms/subtypes and other
genetically/phenotypically related disorders
3. Prenatal diagnosis for known familial mutation
4. Genetic counseling

Inherited ichthyoses are a group of rare genetic skin diseases characterized by hyperkeratosis and/or scaling skin. These manifestations are due to mutations in genes mostly involved in skin barrier formation. Inherited ichthyoses are divided into two major subdivisions: nonsyndromic ichthyoses and syndromic forms. The various forms of ichthyosis are distinguished from one another by: 1) the extent of scaling over the body; 2) the presence or absence and intensity of erythroderma; 3) the mode of inheritance; 4) the character of associated abnormalities. The specific symptoms and severity can vary among individuals with the same form. The most common ichthyoses as ichthyosis vulgaris and recessive X-linked ichthyosis often have a delayed onset compared with the other nonsyndromic ichthyoses.

The test covers known genetic causes of inherited forms of nonsyndromic ichthyoses and a range of disorders with ichthyosis symptoms. Currently, many of the causative genes have not been identified yet.

Nonsyndromic ichthyoses can be inherited in an autosomal dominant, autosomal recessive, or X-linked recessive inheritance pattern.

The ichthyoses are rare disorders occurring in all populations. Incidences vary according to disease type. The most common is ichthyosis vulgaris, with an estimate incidence of 1:250 to 1:1000. The recessive X-linked ichthyosis is the second most common ichthyosis, with a prevalence of 1:2000 to 1:6000.

References:
Oji V et al. Revised nomenclature and classification of inherited ichthyoses: results of the First Ichthyosis Consensus Conference in Sorèze 2009. J Am Acad Dermatol. 2010;63(4):607-641. doi:10.1016/j.jaad.2009.11.020. PMID: 20643494
Richard G. Autosomal Recessive Congenital Ichthyosis. 2001 Jan 10 [Updated 2017 May 18]. In: Adam MP, Ardinger HH, Pagon RA, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2020. Available from: https://www.ncbi.nlm.nih.gov/books/NBK1420/
Takeichi T, Akiyama M. Inherited ichthyosis: Non-syndromic forms. J Dermatol. 2016;43(3):242-251. doi:10.1111/1346-8138.13243. PMID: 26945532