Early Infantile Epileptic Encephalopathy (EIEE)

Contact details Introduction Molecular Genetics Service The early infantile epileptic encephalopathies (EIEE) are a group of disorders Level 6, Barclay House characterized by early onset seizures and developmental delay. Many are associated 37 Queen Square with intractable seizures, severe developmental delay and require lifelong care. Early London, WC1N 3BH mortality is common amongst severely affected individuals due to seizures and/or T +44 (0) 20 7762 6888 respiratory tract infections. F +44 (0) 20 7813 8578 An increasing number of individual genetic disorders are now recognised to cause EIEE. In only a small subset of the disorders is the clinical phenotype sufficiently Samples required recognisable or distinctive to allow targeted testing of specific .  5ml venous blood in plastic EDTA Referrals bottles (>1ml from neonates)  A completed DNA request card  Patients with EIEE and insufficient clinical features to target testing to a should accompany all samples single gene. Clinical details must be provided with all referrals.

Patient details  Targeted parental testing to clarify inheritance and potential significance of relevant variants detected in the proband. To facilitate accurate testing and reporting please provide patient  Mutation testing can be offered to the relatives of EIEE patients once a disease demographic details (full name, date of causing mutation has been identified. birth, address and ethnic origin), details of any relevant family history and full Service offered contact details for the referring clinician Next generation sequencing of 82 genes (see list below) with mutation confirmation by Sanger sequencing. Updated List of genes included in version 10 panel ADSL, ALG13, ARHGEF9, ARX, ATP1A3, ATRX, BRAT1, CDKL5, CHD2, CHRNA2, CHRNA4, CHRNB2, CLN5, CLN6, CLN8, CNTNAP2, DNM1, DOCK7, DYRK1A, EHMT1, FOXG1, GABRA1, GABRB3, GATAD2B, GNAO1, GRIN1, GRIN2A, GRIN2B, HCN1, IQSEC2, KCNA2, KCNB1, KCNC1, KCNQ2, KCNT1, KIAA1279 (KIF1BP), KIAA2022, LGI1, MAGI2, MBD5, MECP2, MEF2C, MFSD8, NACC1, NRXN1, PCDH19, PIGA, PIGN, PLCB1, PNKP, POLG, PRRT2, PURA, QARS, SCN1A, SCN1B, SCN2A, SCN8A, SETD5, SIK1, SLC12A5, SLC13A5, SLC16A2, SLC25A22, SLC2A1, SLC35A2, SLC6A1, SLC9A6, SMC1A, SPTAN1, STX1B, STXBP1, SYNGAP1, TBC1D24, TCF4, TPP1, UBE2A, UBE3A, UNC80, WDR45, WWOX, ZEB2 List of genes removed from panel CBL, CSNK1G1, FASN, GABBR2, PIGQ, RYR3 Technical Mutation screening is carried out by next generation sequencing with library preparation using a Sure Select XT custom kit followed by sequencing on the Illumina MiSeq. Data is analysed using an in-house pipeline with all mutations confirmed by Sanger sequencing. Target reporting time

4 months for a full mutation screen in an index case (next generation sequencing). 4 weeks for family follow-up testing. Please contact the laboratory for urgent cases.