Whole-genome analysis of monozygotic twins discordant for type 1 narcolepsy

Narcolepsy type 1 (NT1) is a rare and chronic neurological disease characterized by sudden sleep attacks, overwhelming daytime drowsiness, and cataplexy. To contribute to the understanding of NT1 genetic causes, here we describe a whole-genome analysis of a monozygotic twin pair discordant for NT1. Our study revealed that although both twins have the same pathogenic mutations in NT1 associated genes (such as HLA-DQB1*06:02:01, HLA-DRB1*11:01:02/*15:03:01) the unaffected twin has mutations in genes outside the HLA loci that could be suppressing the NT1 phenotype. These results support the notion that NT1 has an immunological basis but that protective mutations in non-HLA might interfere with the clinical manifestation of the disease.

[1]  T. Scammell,et al.  The neurobiological basis of narcolepsy , 2018, Nature Reviews Neuroscience.

[2]  E. Mignot,et al.  Autoimmunity to hypocretin and molecular mimicry to flu in type 1 narcolepsy , 2018, Proceedings of the National Academy of Sciences.

[3]  Thomas Colthurst,et al.  A universal SNP and small-indel variant caller using deep neural networks , 2018, Nature Biotechnology.

[4]  Benjamin Neale,et al.  A synthetic-diploid benchmark for accurate variant calling evaluation , 2018, Nature Methods.

[5]  Christopher T. Saunders,et al.  Strelka2: fast and accurate calling of germline and somatic variants , 2018, Nature Methods.

[6]  Jia Gu,et al.  fastp: an ultra-fast all-in-one FASTQ preprocessor , 2018, bioRxiv.

[7]  D. Posthuma,et al.  Functional mapping and annotation of genetic associations with FUMA , 2017, Nature Communications.

[8]  M. Silber,et al.  Comorbidities in a community sample of narcolepsy. , 2017, Sleep medicine.

[9]  James T. Robinson,et al.  Variant Review with the Integrative Genomics Viewer. , 2017, Cancer research.

[10]  E. Mignot,et al.  Autoimmunity in narcolepsy , 2017, Current opinion in pulmonary medicine.

[11]  M. Partinen,et al.  Incidence of narcolepsy after H1N1 influenza and vaccinations: Systematic review and meta-analysis. , 2017, Sleep medicine reviews.

[12]  S. Gammeltoft,et al.  Monozygotic twins discordant for narcolepsy type 1 and multiple sclerosis , 2016, Neurology: Neuroimmunology & Neuroinflammation.

[13]  Hans-Jürgen Bandelt,et al.  HaploGrep 2: mitochondrial haplogroup classification in the era of high-throughput sequencing , 2016, Nucleic Acids Res..

[14]  F. Cunningham,et al.  The Ensembl Variant Effect Predictor , 2016, bioRxiv.

[15]  K. Hirata,et al.  A polymorphism in CCR1/CCR3 is associated with narcolepsy , 2015, Brain, Behavior, and Immunity.

[16]  John G. Cleary,et al.  Comparing Variant Call Files for Performance Benchmarking of Next-Generation Sequencing Variant Calling Pipelines , 2015, bioRxiv.

[17]  E. Mignot,et al.  Genome Wide Analysis of Narcolepsy in China Implicates Novel Immune Loci and Reveals Changes in Association Prior to Versus After the 2009 H1N1 Influenza Pandemic , 2013, PLoS genetics.

[18]  Mauricio O. Carneiro,et al.  From FastQ Data to High‐Confidence Variant Calls: The Genome Analysis Toolkit Best Practices Pipeline , 2013, Current protocols in bioinformatics.

[19]  M. Johns,et al.  A new method for measuring daytime sleepiness: the Epworth sleepiness scale. , 1991, Sleep.

[20]  Paul Shaman,et al.  University of pennsylvania smell identification test: A rapid quantitative olfactory function test for the clinic , 1984, The Laryngoscope.

[21]  B. Nolan Elevated Tribbles homolog 2specific antibody levels in narcolepsy patients , 2011 .