Molecular Neurobiology (2019) 56:8008–8017 https://doi.org/10.1007/s12035-019-1630-2 Uveitis and Multiple Sclerosis: Potential Common Causal Mutations Alejandra de-la-Torre1 & Claudia T. Silva-Aldana2 & Juliana Muñoz-Ortiz1,3 & Laura B. Piñeros-Hernández2 & Oscar Otero3 & Alejandra Domínguez1 & León A. Faciolince1,3 & Mauricio Arcos-Holzinger1 & Claudio Mastronardi4 & Nora Constanza Contreras-Bravo2 & Carlos Martín Restrepo2 & Mauricio Arcos-Burgos5 Received: 11 March 2019 /Accepted: 26 April 2019 /Published online: 3 June 2019 # The Author(s) 2019 Abstract Uveitis, defined as inflammation of the uveal tract of the eye, is a leading cause of blindness and visual impairment throughout the world. The etiology of uveitis is complex, and autoimmunity plays a major role in its pathogenesis. Intermediate uveitis (IU), a subtype of ocular inflammation, has been associated with systemic autoimmune disorders, specifically with multiple sclerosis (MS). This article reports a rare three-generation family with several members affected by IU (four siblings) and comorbid MS (two siblings fulfilling MS diagnostic criteria and a third sibling presenting some neurological symptoms). Based on the clinical findings, we captured and sequenced whole exomes of seven pedigree members (affected and unaffected). Using a recessive model of transmission with full penetrance, we applied genetic linkage analysis to define minimal critical regions (MCRs) in suggestive or nominal regions of linkage. In these MCRs, we defined functional (some pathogenic), novel, and rare mutations that segregated as homozygous in affected and heterozygous in unaffected family members. The genes harboring these mutations, including DGKI, TNFRSF10A, GNGT1, CPAMD8,andBAFF, which are expressed in both eye and brain tissues and/or are related to autoimmune diseases, provide new avenues to evaluate the inherited causes of these devastating autoimmune conditions. Keywords Uveitis . Multiple sclerosis . Genetics . Mutations . Whole exome sequencing . Pedigree Introduction incidence of uveitis varies between 17.4 and 52.4 new cases per 100,000, and the prevalence is between 38 and 714 per Uveitis is inflammation of the eye’s uveal tract, which in- 100,000. This disease causes 2.8–10% of all cases of blind- cludes the iris, ciliary body, and choroid [1]. The annual ness and visual impairment worldwide, and severity depends on factors such as chronicity and whether or not adjacent Alejandra de-la-Torre, Claudia T. Silva-Aldana and Mauricio Arcos- tissues, such as the retina, optic nerve, and vitreous, are affect- Burgos contributed equally to this work. ed [2–5]. * Alejandra de-la-Torre The Uveitis Nomenclature Standardization (SUN) [email protected] Working Group and the International Uveitis Study Group * Mauricio Arcos-Burgos (IUSG) classify uveitis according to the anatomical location [email protected] of the inflammatory process, i.e., anterior uveitis (iritis, iridocyclitis, and anterior cyclitis), intermediate uveitis (pars 1 Grupo de investigación en neurociencias (NEUROS), Escuela de planitis, posterior cyclitis, and hyalitis), posterior uveitis (fo- Medicina y Ciencias de la Salud, Universidad del Rosario, cal, multifocal, or diffuse choroiditis, chorioretinitis, retinitis, Bogotá, Colombia and neuroretinitis), and panuveitis (anterior chamber, vitreous, 2 ‐ Center For Research in Genetics and Genomics CIGGUR, retina, and choroid) [6–9]. GENIUROS Research Group, School of Medicine and Health Sciences, Universidad del Rosario, Bogotá, Colombia The etiology of uveitis is complex and involves con- 3 fined autoimmune processes [10], systemic autoimmune Escuela Superior de Oftalmología, Instituto Barraquer de América, Bogotá, Colombia diseases (e.g., multiple sclerosis, Behçet’s disease), infec- 4 tious diseases (e.g., Toxoplasma gondii, Mycobacterium INPAC Research Group, Fundación Universitaria Sanitas, Bogotá, Colombia tuberculosis, Herpes virus,andTreponema pallidum), 5 and inherited genetic susceptibility [11–13]. Previous Grupo de Investigación en Psiquiatría (GIPSI), Departamento de Psiquiatría, Instituto de Investigaciones Medicas (IIM), Facultad de studies reported association of the susceptibility to devel- Medicina, Universidad de Antioquia, Medellin, Colombia op uveitis with polymorphisms in the human lymphocyte Mol Neurobiol (2019) 56:8008–8017 8009 antigen (HLA) class II genes, interleukins 10 and 6 (IL10 and IL6, respectively), tumoral necrosis factor (TNF), transforming growth factor beta 1 and 2 (TGFB1 and TGFB2, respectively), transforming growth factor beta re- ceptor 3 (TGFBR3), interferon gamma (INFG), interleukin 2 receptor subunit alpha (IL2RA), and cytotoxic T lym- phocyte protein 4 (CTLA4), among others [11]. In this article, specific focus is brought to intermedi- ate uveitis (IU) which is the most frequent type of uve- itis associated with MS (61–80%) [14–16]. One expla- nation attributes this association to the ontogenetic rela- tionship between nervous and ocular tissues. An exam- ple of this is the MS demyelination process, which af- Fig. 1 Genealogy segregating intermediate uveitis (IU) and multiple scle- fects both the central nervous system and neuro- rosis (MS). Intermediate uveitis (black signals condition of interest). ophthalmic tracts [16] producing histopathological and Comorbid multiple sclerosis (asterisk) clinical findings common to IU and MS. These include T cells, especially T helper lymphocytes (Th), which Methods infiltrate areas surrounding retinal vessels creating pa- thognomonic histopathological changes known as Bsnow Patients banking^ or Bstrings of pearls^ [17]. Interestingly, pa- tients with MS have autoreactive T cells and antibodies We studied three generations of a family composed of eight directed against glial proteins that are also detected in individuals. Four members of the family were affected by IU snow banking formations. Some authors explain this by (EMU003, EMU004, EMU005, and EMU002) of which two the presence of autoreactive T cells directed toward a also fulfilled diagnostic criteria of MS (EMU005 and common glial epitope present in MS and/or IU patients EMU002), and a third had neurological symptoms suggesting [18]. MS comorbidity (EMU004) (Fig. 1). Briefly, the family is Given that IU and MS are rare disorders, it is unusu- composed of unaffected parents, four siblings, two women al to find patients suffering from both conditions and and two men, the husband of one of the women, and a grand- even less common to find several siblings affected by daughter. IU in all siblings began in childhood (6 to 12 years both conditions. In this manuscript, we report a pedigree old) with episodes of ocular inflammation. A more aggressive with four siblings affected by IU of which two present development of the disease, with a higher incidence of com- sufficient symptoms for the diagnosis of MS (as stated plications, including retinal detachment, was observed in by the revised 2017 McDonald criteria for the diagnosis women (Fig. 2). Consequently, more intensive therapies were of MS) and one presents neurological symptoms that do applied to females (higher doses of steroids and immunosup- not fulfill the McDonald criteria. We hypothesize that pressive drugs, such as methotrexate) (Table 1). Three of the rare/novel genetic variants of major effect shape shared siblings developed neurologic symptoms, including paresthe- genetic susceptibility to both IU and MS. To test this sia and muscular weakness (Table 2). Magnetic resonance hypothesis, we applied whole exome capture and se- imaging of the brain and cervical spine showed the presence quencing and used the resulting genomic variation to of periventricular-demyelinating plaques in affected women determine genetic linkage of potential novel and rare (Figs. 3, 4,and5). Similar to the ocular disease, the neurolog- pathogenic causal mutations with the phenotype. ical symptoms were more aggressive in women than in men Fig. 2 Retinal fluorescein angiography and fundus photography detachment (black arrows). c Intraretinal hemorrhage (asterisk) and reti- EMU005. a Papillitis (circle), cystoid macular edema (white arrow), nal detachment (black arrow) perivasculitis (black arrows), and retinitis (asterisk). b Exudative retinal 8010 Mol Neurobiol (2019) 56:8008–8017 (multiple hospitalizations and treatment with interferon were necessary for women). Females EMU005 and EMU002 ful- filled the revised 2017 McDonald criteria for the diagnosis of MS (Table 2). ids, prednisolone, ids, prednisolone, t, methotrexate Whole Exome Capture, Sequencing, and Bioinformatic Analysis Three methods were used to quantify and qualify DNA: (1) and systemic immunosuppressant, steroids. Systemic corticosteroids, prednisolone, and systemic immunosuppressan methotrexate (higher doses). Systemic corticostero Systemic corticostero and systemic immunosuppressant, methotrexate (higher doses). DNA purity was checked using a NanoDrop spectrophotom- Observation Topic and injected periocular Topic and injected periocular steroids. Topic and injected periocular steroids. eter (Thermo Scientific, Waltham, MA, USA) (OD 260/280 ratio); (2) DNA degradation and contamination were moni- tored on 1% agarose gels; (3) DNA concentration was mea- OS 20/20 OS 20/50 OS 20/20 OS 20/30 sured using a Qubit fluorometer (Thermo Scientific, Waltham, MA, USA). DNAsampleswithOD260/280ratiosbetween1.8and2.0 and concentration above 1.0 μgwereusedtopreparese- quencing libraries. Library preparation for sequencing: Liquid-phase