Targeted Next Generation Sequencing reveals previously unidentified TSC1 and TSC2 mutations.
BACKGROUND
Tuberous sclerosis complex (TSC) is an autosomal dominant disorder caused by mutations in TSC1 and TSC2. Conventional DNA diagnostic screens identify a TSC1 or TSC2 mutation in 75 - 90% of individuals categorised with definite TSC. The remaining individuals either have a mutation that is undetectable using conventional methods, or possibly a mutation in another as yet unidentified gene.


METHODS
Here we apply a targeted Next Generation Sequencing (NGS) approach to screen the complete TSC1 and TSC2 genomic loci in 7 individuals fulfilling the clinical diagnostic criteria for definite TSC in whom no TSC1 or TSC2 mutations were identified using conventional screening methods.


RESULTS
We identified and confirmed pathogenic mutations in 3 individuals. In the remaining individuals we identified variants of uncertain clinical significance. The identified variants included mosaic changes, changes located deep in intronic sequences and changes affecting promoter regions that would not have been identified using exon-only based analyses.


CONCLUSIONS
Targeted NGS of the TSC1 and TSC2 loci is a suitable method to increase the yield of mutations identified in the TSC patient population.
Department of Clinical Genetics, Ee-2426, Erasmus Medical Center, Wytemaweg 80, 3015, Rotterdam, CN, The Netherlands. m.nellist@erasmusmc.nl.
Mark
M
Nellist
Center for Biomics, Erasmus Medical Center, Wytemaweg 80, 3015, Rotterdam, CN, The Netherlands. r.w.w.brouwer@erasmusmc.nl.
Rutger W W
RW
Brouwer
Center for Biomics, Erasmus Medical Center, Wytemaweg 80, 3015, Rotterdam, CN, The Netherlands. c.kockx@erasmusmc.nl.
Christel E M
CE
Kockx
Department of Clinical Genetics, Ee-2426, Erasmus Medical Center, Wytemaweg 80, 3015, Rotterdam, CN, The Netherlands. m.plandsoen@erasmusmc.nl.
Monique
M
van Veghel-Plandsoen
Department of Clinical Genetics, Ee-2426, Erasmus Medical Center, Wytemaweg 80, 3015, Rotterdam, CN, The Netherlands. c.hermans@erasmusmc.nl.
Caroline
C
Withagen-Hermans
Department of Clinical Genetics, Ee-2426, Erasmus Medical Center, Wytemaweg 80, 3015, Rotterdam, CN, The Netherlands. p.bakker@erasmusmc.nl.
Lida
L
Prins-Bakker
Department of Clinical Genetics, Ee-2426, Erasmus Medical Center, Wytemaweg 80, 3015, Rotterdam, CN, The Netherlands. m.hoogeveen-westerveld@erasmusmc.nl.
Marianne
M
Hoogeveen-Westerveld
Department of Clinical Genetics, Ee-2426, Erasmus Medical Center, Wytemaweg 80, 3015, Rotterdam, CN, The Netherlands. a.mrsic@erasmusmc.nl.
Alan
A
Mrsic
Department of Clinical Genetics, Ee-2426, Erasmus Medical Center, Wytemaweg 80, 3015, Rotterdam, CN, The Netherlands. m.m.p.vandenberg@erasmusmc.nl.|Department of Ophthalmology, Erasmus Medical Center, Wytemaweg 80, 3015, Rotterdam, CN, The Netherlands. m.m.p.vandenberg@erasmusmc.nl.
Mike M P
MM
van den Berg
Department of Clinical Genetics, Ee-2426, Erasmus Medical Center, Wytemaweg 80, 3015, Rotterdam, CN, The Netherlands. a.koopmans@erasmusmc.nl.|Department of Ophthalmology, Erasmus Medical Center, Wytemaweg 80, 3015, Rotterdam, CN, The Netherlands. a.koopmans@erasmusmc.nl.
Anna E
AE
Koopmans
Department of Neurology, Sophia Children's Hospital, Erasmus Medical Center, Wytemaweg 80, 3015, Rotterdam, CN, The Netherlands. m.c.y.dewit@erasmusmc.nl.
Marie-Claire
MC
de Wit
Department of Pediatric Neurology, Brain Center Rudolf Magnus, University Medical Center Utrecht, 3508, Utrecht, EA, The Netherlands. f.e.jansen@umcutrecht.nl.
Floor E
FE
Jansen
Department of Clinical Genetics, Ee-2426, Erasmus Medical Center, Wytemaweg 80, 3015, Rotterdam, CN, The Netherlands. j.a.maat@erasmusmc.nl.
Anneke J A
AJ
Maat-Kievit
Department of Clinical Genetics, Ee-2426, Erasmus Medical Center, Wytemaweg 80, 3015, Rotterdam, CN, The Netherlands. a.vandenouweland@erasmusmc.nl.
Ans
A
van den Ouweland
Department of Clinical Genetics, Ee-2426, Erasmus Medical Center, Wytemaweg 80, 3015, Rotterdam, CN, The Netherlands. d.halley@erasmusmc.nl.
Dicky
D
Halley
Department of Clinical Genetics, Ee-2426, Erasmus Medical Center, Wytemaweg 80, 3015, Rotterdam, CN, The Netherlands. a.deklein@erasmusmc.nl.
Annelies
A
de Klein
Center for Biomics, Erasmus Medical Center, Wytemaweg 80, 3015, Rotterdam, CN, The Netherlands. w.vanijcken@erasmusmc.nl.
Wilfred F J
WF
van IJcken
D000293:Adolescent; D002648:Child; D004252:DNA Mutational Analysis; D056426:Genetic Loci / Q000235:genetics; D023281:Genomics; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D008875:Middle Aged; D009154:Mutation; D014402:Tuberous Sclerosis / Q000235:genetics; D000077004:Tuberous Sclerosis Complex 1 Protein; D000077005:Tuberous Sclerosis Complex 2 Protein; D025521:Tumor Suppressor Proteins / Q000235:genetics*
C000624650:TSC1 protein, human; C000624653:TSC2 protein, human; D000077004:Tuberous Sclerosis Complex 1 Protein; D000077005:Tuberous Sclerosis Complex 2 Protein; D025521:Tumor Suppressor Proteins