• Clinical delineation, sex differences, and genotype–phenotype correlation in pathogenic KDM6A variants causing X-linked Kabuki syndrome type 2

      Faundes, Víctor; Goh, Stephanie; Akilapa, Rhoda; Bezuidenhout, Heidre; Bjornsson, Hans T.; Bradley, Lisa; Brady, Angela F.; Brischoux-Boucher, Elise; Brunner, Han; Bulk, Saskia; et al. (Nature Publishing Group US, 2021-03-05)
      Abstract: Purpose: The variant spectrum and the phenotype of X-linked Kabuki syndrome type 2 (KS2) are poorly understood. Methods: Genetic and clinical details of new and published individuals with pathogenic KDM6A variants were compiled and analyzed. Results: Sixty-one distinct pathogenic KDM6A variants (50 truncating, 11 missense) from 80 patients (34 males, 46 females) were identified. Missense variants clustered in the TRP 2, 3, 7 and Jmj-C domains. Truncating variants were significantly more likely to be de novo. Thirteen individuals had maternally inherited variants and one had a paternally inherited variant. Neonatal feeding difficulties, hypoglycemia, postnatal growth retardation, poor weight gain, motor delay, intellectual disability (ID), microcephaly, congenital heart anomalies, palate defects, renal malformations, strabismus, hearing loss, recurrent infections, hyperinsulinism, seizures, joint hypermobility, and gastroesophageal reflux were frequent clinical findings. Facial features of over a third of patients were not typical for KS. Males were significantly more likely to be born prematurely, have shorter stature, and severe developmental delay/ID. Conclusion: We expand the KDM6A variant spectrum and delineate the KS2 phenotype. We demonstrate that the variability of the KS2 phenotypic depends on sex and the variant type. We also highlight the overlaps and differences between the phenotypes of KS2 and KS1.
    • Clinical utility of genetic testing in 201 preschool children with inherited eye disorders

      Lenassi, Eva; Clayton-Smith, Jill; Douzgou, Sofia; Ramsden, Simon C.; Ingram, Stuart; Hall, Georgina; Hardcastle, Claire L.; Fletcher, Tracy A.; Taylor, Rachel L.; Ellingford, Jamie M.; et al. (Nature Publishing Group US, 2019-12-18)
      Abstract: Purpose: A key property to consider in all genetic tests is clinical utility, the ability of the test to influence patient management and health outcomes. Here we assess the current clinical utility of genetic testing in diverse pediatric inherited eye disorders (IEDs). Methods: Two hundred one unrelated children (0–5 years old) with IEDs were ascertained through the database of the North West Genomic Laboratory Hub, Manchester, UK. The cohort was collected over a 7-year period (2011–2018) and included 74 children with bilateral cataracts, 8 with bilateral ectopia lentis, 28 with bilateral anterior segment dysgenesis, 32 with albinism, and 59 with inherited retinal disorders. All participants underwent panel-based genetic testing. Results: The diagnostic yield of genetic testing for the cohort was 64% (ranging from 39% to 91% depending on the condition). The test result led to altered management (including preventing additional investigations or resulting in the introduction of personalized surveillance measures) in 33% of probands (75% for ectopia lentis, 50% for cataracts, 33% for inherited retinal disorders, 7% for anterior segment dysgenesis, 3% for albinism). Conclusion: Genetic testing helped identify an etiological diagnosis in the majority of preschool children with IEDs. This prevented additional unnecessary testing and provided the opportunity for anticipatory guidance in significant subsets of patients.
    • IL-17A both initiates, via IFNγ suppression, and limits the pulmonary type-2 immune response to nematode infection

      Ajendra, Jesuthas; Chenery, Alistair L.; Parkinson, James E.; Chan, Brian H. K.; Pearson, Stella; Colombo, Stefano A. P.; Boon, Louis; Grencis, Richard K.; Sutherland, Tara E.; email: tara.sutherland@manchester.ac.uk; Allen, Judith E.; orcid: 0000-0002-3829-066X; email: judi.allen@manchester.ac.uk (Nature Publishing Group US, 2020-07-07)
      Abstract: Nippostrongylus brasiliensis is a well-defined model of type-2 immunity but the early lung-migrating phase is dominated by innate IL-17A production. In this study, we confirm previous observations that Il17a-KO mice infected with N. brasiliensis exhibit an impaired type-2 immune response. Transcriptional profiling of the lung on day 2 of N. brasiliensis infection revealed an increased Ifng signature in Il17a-KO mice confirmed by enhanced IFNγ protein production in lung lymphocyte populations. Depletion of early IFNγ rescued type-2 immune responses in the Il17a-KO mice demonstrating that IL-17A-mediated suppression of IFNγ promotes type-2 immunity. Notably, later in infection, once the type-2 response was established, IL-17A limited the magnitude of the type-2 response. IL-17A regulation of type-2 immunity was lung-specific and infection with Trichuris muris revealed that IL-17A promotes a type-2 immune response in the lung even when infection is restricted to the intestine. Together our data reveal IL-17A as a major regulator of pulmonary type-2 immunity such that IL-17A supports early development of a protective type-2 response by suppression of IFNγ but subsequently limits excessive type-2 responses. A failure of this feedback loop may contribute to conditions such as severe asthma, characterised by combined elevation of IL-17 and type-2 cytokines.